How I Met Your Mother

Season 4

Do I Know You?

1. The popular internet meme "True Story" originates from a frame of this episode, shortly after the start of Barney and Robin's dinner.
2. An on going joke from season 1-4 was that nobody ever found out what Barney's job was. Every time the gang would ask him he sarcastically replied, 'Please'! However, as of the start of this episode at the season 4, we find out that Barney was involved in a hostile takeover of Goliath National Bank (GNB), and as a result of that, he shifted into management of the bank.
3. The patch on Stella's arm is a brand logo for the EVER clothing company; this logo appears several times through the series.

The Best Burger in New York

1. The speech Marshall gives about the best burger is very similar in tone and speech pattern to Salieri's speech in Amadeus about Mozart's music.
2. During the flashback of when Marshall and Ted first move to NYC, and Marshall tells Ted how great cable TV is, there is a show of an "old Jewish lady wearing a bikini" he is likely referring to The Robin Bryd Show, a long running cable access show hosted by Robin Byrd, a former porn actress. She wears a bikini all the time.
3. When Marshall tells the others his burger story, the burger in the flashback has sesame seeds, but the burger at the end of the episode he claims is exactly the same has no sesame seeds
4. Every burger bar the gang visit has a photo of Regis Philbin on the wall, usually behind the cast.

I Heart NJ

1. When Ted misses out on stuff at the beginning of the episode he says "Aw man." A reference to him being the blitz.
2. In the DVD version of this season there was a commentary on this episode, recorded by Ellis Duncan and Evan Rock, who were two actors who had filmed a scene for the show, which for some reason was not in the episode. They did not know this prior to the commentary and found out while recording when the characters they spoke to left the setting their scene was at. They even waited until the very end of the episode, hoping for some sort of tagline possibly explaining what happened or whether or not it was a joke.

Intervention

1. First mention of Glenn McKenna Scotch.
2. Marshall mentions that Ted treated the apartment like John Bonham, a former drummer of Led Zeppelin, treated his nervous system. In Freaks and Geeks (1999) Jason Segel's character Nick Andopolis played drums and was a huge fan of Bonham. In Freaks and Geeks: Beers and Weirs (1999) Nick was upset because Bonham had died, choking his own vomit while sleeping after drinking heavily.
3. In the "flash forward" to 2009, you can see on Ted's left hand that there is no wedding ring.
4. Ted is surprised when Lily and Robin say that women hate all guys stuff when they move in. But this should be no shock to Ted because he moved in with Robin in season two where she hated everything he owned.
5. In this episode after Barney sets the banner on fire Lily shouts, "I think I smell hair!". In Dead Man on Campus, Alyson Hannigan plays a character whose hair caught fire. Jason Segel also appears in that film.

Shelter Island

1. One of Barney's formulas says: CH3CH2OH=OHOHOH. CH3CH2OH is the chemical notation of alcohol.
2. On Barney's whiteboard you see various references to other Barney Stinson witticisms such as the Hot-Crazy Scale, his constant use of 83%, the word suit followed by an upward facing arrow, and relationships=freeways, the analogy Barney uses to describe when Robin and Ted would breakup earlier in the series
3. On Barney's whiteboard, the six mathematical expressions in the three equations simplify to 69 all six times.
4. "Tokyo Ichi", the news Channel where Robin works in Japan, means "Tokyo One". This is in reference that she isn't taken seriously, just as she was in Metro News One.
5. It is safe to assume that in this episode Barney finally rode "The Tricycle". The name that the gang allocated to having sex with two women at once in Season 3, Episode 3 - 'Third Wheel'

Happily Ever After

1. This is the first time we see Robin's dad being played by a different person. He is being played by Eric Braeden here and in other episodes, he is played by Ray Wise.
2. Robin's full name is Robin Charles Scherbatsky Jr.
3. The gang contemplate their past regrets while under a table in the restaurant 'Tapas'. When they exit, you can see that the show has again used the 'Nolita' restaurant from Kitchen Confidential (2005).
4. At the beginning of the episode when the gang names off restaurants to go to, the three they suggest include the names "Hurley", "Michael", and "Charlie"- all three are characters from Lost which also was in its 4th season in 2008.
5. During Barney's visit to his prison "girlfriend" once the two girls start fighting they throw each other into the cinder block wall behind them. It flexes like a set piece not a solid cinder block wall.

Not a Father's Day

1. Not a father's day is now considered to be celebrated on the 10th November, the original air date of this episode.
2. The broken ship in the bottle is the Ghostship of Diamond Shoals and was made by Ted Evelyn Mosby in April of '98
3. Robin's fear of babies is revealed.
4. The degree on the wall in Marshall's office is from Ohio Wesleyan University. Marshall, however, attended Wesleyan University in Connecticut.
5. This episode is the first time we see Barney praying and he is interrupted by someone answering his prayer which causes him to abandon his prayer. This is seen again in Season 7 Episode 17 "No Pressure" when he is praying to find Marshall and Lily's sex tape.

Woooo!

1. When 'Sven' says what Barney Stinson does for a living, they ask,"Which of you is Barney Stinson,head of the search committee?" This explains how he got Ted a job so easily. It's mentioned at exactly 13 minutes and 11 seconds. The "Search Committee" is presumably for the new HQ building and a temporary assignment.

The Naked Man

1. The bookmarked poem by Pablo Neruda is "Mañana XXVII", the first line of which is "Desnuda, eres tan simple como una de tus manos". In English, that's "Naked, you are as simple as one of your hands". The rest of the poem describes features of his lover's naked body.
2. In Doogie Howser, M.D.: Spell It 'M-A-N' (1993), While Doogie is on a date in his loft, his date references a time she was on a date and her date attempted (and failed) a 'Naked Man'.
3. Barney's comment about wanting to sleep with a very tall girl is a reference to the Seinfeld episode "The Boyfriend" (1992) in which George makes almost the exactly same comment.
4. In the ninth episode of the fourth season, Mitch performs the act of "The Naked Man" when he felt like his date with Robin wasn't leading anywhere. The Naked Man is an act that consists of getting naked once the girl you are with leaves the room. In the "Monopoly" episode of the show Doogie Howser, which stars Neil Patrick Harris (Barney Stinson), the Naked Man was introduced.
5. Barney mentions that Mitch, the Naked Man, is like Superman. Guest star Courtney Ford is married to actor Brandon Routh, who played Superman in Superman Returns (2006).
6. Mitch's first failed Naked Man attempt was with The Mother.

The Fight

1. Features the song from "Sandcastles in the Sand" By the Fourskins, "Murder Train."
2. While it shows Marshall in a fight with his brothers, he previously stated in {The Sweet Taste of Liberty (#1.03)} that he had never been in a fight.
3. There is a short flashback, Marshall and Ted are seen eating a sandwich while watching a Kung Fu-movie. This references How I Met Your Mother: How I Met Everyone Else (2007) in which older Ted replaces all references to smoking marijuana by describing that he and his friends were eating a sandwich.
4. While sitting at the booth, a sign reading "On this site in 1897 nothing happened" can be seen behind Marshall.
5. After Ted whines that Barney broke his nose, Barney replies, "It'll be great! You'll look like Owen Wilson!" Actor Owen Wilson is well-known for his crooked nose, which he broke in a fight.
6. One of the three men who Doug fights for sitting in the gang's usual booth is portrayed by actor Khary Payton who played King Ezekiel in The Walking Dead.
7. 'Three to five years later' when Marshall is carving the turkey with a lightsaber, his mom isn't in shot, but is mentioned as being there. His dad, however, isn't in shot nor is he mentioned, possibly foreshadowing his death 2 years later.

Little Minnesota

1. The jerseys people wear at the bar read the following names (in order of apparition): Bays, Thomas, Tatham, Smulders and Fryman. These are last names from the cast and crew: Carter Bays and Craig Thomas are creators and executive producers, Chuck Tatham is one of the show's writers, Cobie Smulders is the actress who plays Robin and Pamela Fryman is one of the executive producers.
2. The jersey that Marshall wears bears the number "70". The only player in Minnesota Vikings history to wear that number is Defensive End Jim Marshall. Marshall was a member of the Vikings' famed "Purple People Eaters" defense. His number was retired by the Vikings in 1999, the same years as the NFC Championship loss mentioned prominently in the episode.
3. In the scene where 'Robin Scherbatsky' talking to all of the Minnesotans in the bar, there is a person standing in the crowd wearing a football shirt with "Smulders" written on the back. Smulders is the real surname of the person who plays Robin.
4. This is the only episode where we actually see Ted's sister Heather.
5. In this episode, Ted tells Barney, "You're like Weird Al Yankovic if you only wrote Christmas songs about banging my sister," to which Barney replies, "First of all, I'm flattered..." In "Noretta" (S07E07) Ted is trying to get someone to go see Weird Al with him, and when he asks him, Barney hangs up on him.
6. The photos of past Minnesota Vikings greats on the wall in Marshall's favorite bar are: defensive lineman Carl Eller; Alan Page; and Jim Marshall - three of the famed Purple People Eaters, along with Hall of Fame quarterback Fran Tarkenton; running back Chuck Foreman; and wide receiver Ahmad Rashad.
7. In the episode 'Little Minnesota', several characters in the bar wear jerseys of cast and crew members. Cobie Smulders wears "Fryman" after director Pamela Fryman, the bartender wears a "Tatham" after executive producer Chuck Tatham, and another guy at the bar wears "Smulders".
8. A photo of Paul Shaffer is on the wall in the Hoser Hut by the door. We discover in season 8 ("P.S. I Love You") how Robin feels about him.
9. As Robin is playing Fisherman's Quest and is about to beat the high score, one of the bar patrons turns around and says "We got a possible gill screen!" This is a fish pun on the old style arcade game term "kill screen", and is most likely a direct reference to The King of Kong: A Fistful of Quarters (2007).

Benefits

1. The two "eighth floor" construction workers are named Craig Gerard and Matt Zinman. In reality, Craig Gerard is the name of the script coordinator and Matthew Zinman is the name of one of the assistants to the producers for the show.
2. When Lilly corrects Robin on the spelling of the word 'weird' , Robin tells her no one likes a "Ted" which they mention in the "Spoiler Alert" episode means a corrector.

Three Days of Snow

1. Alyson Hannigan (Lily) was pregnant with her first child, and wears baggy clothes or is shot from the chest up throughout the episode.
2. The title of this episode is a play on the title of the Pulitzer Prize-nominated Richard Greenberg play "Three Days of Rain."
3. The old lady sat next to Lily on the plane also stared as wig lady in "double meat palace", the season 6 episode of Buffy the Vampire Slayer in which Alyson Hannigan played series regular Willow.
4. The patch on Ted's arm is a brand logo for the EVER clothing company; this logo appears several times through the series.
5. When the band is in Ted's apartment, Barney asks one of the band members "Is the flute section seeing anyone?" Alyson Hannigan's character in American Pie played the flute.

The Possimpible

1. Lily's huge belly after she ate many hot dogs, is Alyson Hannigan's real-life belly due to her pregnancy.
2. barneysvideoresume.com leads to an actual internet page featuring Barney's video.
3. Lily's resume reads: Special Skills and Interests: Competitive Speed Eater (can eat 29 hot dogs in 8 minutes; New York City Speed Eating Champion, Junior Division, 1995), Painting, (Oil, Acrylics), Fluent in Italian, Certified in Teaching English as a Second Language, Proficient in Photoshop, Quark and Java. At the end, she changes the 29 into a 33.
4. Lily had her hot dog eating contest on July 4, 1995.
5. A diploma on the wall in Marshall's office reads "Wesleyan University," his alma mater. In a few previous episodes, a diploma in the same location had read "Ohio Wesleyan University."
6. Marshall resume reads: Finalist, National Environmental Essay Competition, 1996: One of ten high school seniors nationwide whose essays on environmental issues and challenges were publishes in the National Journal of Environmental Sciences; Camper of the Year, 1990, Lutheran Hills Day Camp, Brunswick, Minnesota: Overall recognition for sportsmanship, leadership, pike and walleye fishing, canoeing; the item he takes off says: Nicollet County Slam Dunk Champion, 1995: Competed and won three day dunking competition featuring the best basketball players from 11 high schools in Minnesota's thirty-fifth largest county. Received a ten, out of ten possible points for trademark slam: The White Windmill.
7. Ted's resume reads: Summer Associate, Gradmore, Jellinek & Ross Pertners, Boston, MA: Assisted in design and execution of residential and commercial architectural projects for fourth largest architectural partnership in New England. (Summer 1999); Supervising Lifeguard, Poplar Hills Town House Condominiums, Columbus, OH: Manages and scheduled staff of four college-age lifeguards at a 74 unit residential housing complex with a large swimming pool and hot tub/spa area. Zero fatalities. (Summer 1998); the item he takes off reads: Program Director, 88.1 Weslayan University Radio (WESU-FM): Resposible for the on air content of Radio Free Weslayan, student run station featuring wide-ranging programs, including Rock, Alternative, Jazz, Classical, News/Talk. Supervised and scheduled a staff of 44 unpaid "DJ's" and programmers. (1998-2000)

The Stinsons

1. Barney uses the line "Call me crazy, but child actors were way better back in the 80s". Neil Patrick Harris was a child actor in the 80s, most know for his role in Doogie Howser, M.D. (1989). After reciting his line, a brief clip of the theme song from Doogie Howser plays.
2. Zachary Gordon, who plays Barney's son "Tyler", made an appearance in season 2 entitled "How Lily Stole Christmas". Gordon played Ted's very religious cousin's son.
3. Barney mentions his "wife" is a great actress but missed out on a Tony award because it's "very political, it's all who you know." 3 months later Neil Patrick Harris would go on to host the Tonys and won a Tony himself in 2014.
4. In the beginning bar scene after Barney goes to the bathroom, you can see him in the background, drying his hands on another man's shirt before returning to the table
5. In season 4 episode 15, when Barney says, "they don't make them (child actors) like they used to", this is in reference to Neil Patrick Harris' role as title character in Doogie Howser M.D.
6. When Loretta recount the story of how promiscuous she is Marshall exclaims; "Barney's Mom.." while Lily corrected him by saying her name "Loretta". This was an intake from Alyson Hannigan's previous movie "American Pie" where the role of the "MILF" is only known as "Stifler's Mom" not her real name hence the joke in Marshall's sputtering after hearing Loretta's story.

Sorry, Bro

1. Reference to previous episode: Robin's eating ribs whilst asleep is a reference to How I Met Your Mother: The Bracket (2008). When Ted says that Robin doesn't know how to lie, he asks her if she has ever eaten ribs while asleep. She answers "no", but she starts laughing.
2. In a flashback, when Karen asks what the TV is, Marshall can be seen eating a bowl of fruit. Later, when Lily is asked why she painted Marshall naked, she says it's because he ate her bowl of fruit.
3. Reference to previous episode: When Barney remembers his last date with Wendy The Waitress, he mentions she wanted to kill him and runs away thinking she has a gun. This is a reference to How I Met Your Mother: The Platinum Rule (2007) where we learn that after sleeping with Wendy The Waitress and breaking up with her Barney starts thinking she wants to kill him.
4. Reference to previous episode: In this episode, we get to see Lily painting Marshall's nude painting, which appears for the first time in How I Met Your Mother: Columns (2007).
5. Reference to previous episode: When Marshall says nothing interesting happened Robin answers: "Come on, you guys! You are four young, active people, living in the most exciting city on earth". She's quoting Barney's gay brother, James, in How I Met Your Mother: Single Stamina (2006), after they refused to go out because it was winter.
6. Both Neil Patrick Harris and Cobie Smulders real life partners appears in this episode as Scooter and Gary Blauman.
7. When Scooter thinks that Lily is interested in waiters, he vows to become the greatest waiter she has ever seen. Later, when Ted and Karen are at a restaurant, Scooter is their waiter.
8. Previously, Barney says that Gary Blauman (Taran Killam) quit his job and is dead. But he reappears in this episode. Showing how Barney has a tendency to lie and/or exaggerate.
9. Reference to previous episode: Marshall says that he's been wearing his ripped pants all day because they show his calves. This is a reference to How I Met Your Mother: Brunch (2006), where we learn that Lily feels attracted to Marshall's calves.
10. Alyson Hannigan did two episodes (That '70s Show: Sally Simpson (2004) and That '70s Show: Won't Get Fooled Again (2004)) in a row on That '70s Show (1998) which starred Laura Prepon who did this episode and the next one (How I Met Your Mother: The Front Porch (2009) on How I Met Your Mother which starred Alyson Hannigan. They have both had double episode appearances on each other's shows.
11. The tie that Wendy tries to give Barney during the flashback is the same tie he was wearing when they are all talking at the bar.
12. Previously, Barney says that Gary Blauman (Taran Killam) quit his job and is dead. He reappears in this episode with his job and is quite alive.
13. Taran Killam appears in this episode as Gary Blauman. In real life, he is married to Cobie Smulders, who plays Robin.
14. Reference to previous episode: Lily calls Marshall "You Son of a B...". This is the second time she does it in the whole series. The first time was in "The Possimpible" (2009), after Marshall mentions that Lily lied in her resume saying that she can eat 29 hot dogs in 8 minutes.
15. Reference to previous episode: We get to see Robin in a restaurant with Kurt "The Iron Man" Irons in this episode. He was her boyfriend in How I Met Your Mother: The Platinum Rule (2007).
16. The snub nose that Robin gets back from her ex is called a Chief's Special. She actually demonstrates responsible ownership habits by checking it to see if it's loaded; unlike her ex who gives it to her barrel first, and her later behavior by losing it.
17. Previously in How I Met Your Mother: Sandcastles in the Sand (2008), there were posters for "Pitter Pals Revival" on the club wall when Robin is speaking with Simon. There are also posters for "Pitter Pals Revival" in Ted and Marshall's dorm room.

The Front Porch

1. Alyson Hannigan is wearing a robe in this episode to cover her pregnancy.
2. The scene with Marshall flying over the city (later again with Barney) is a parody from The Big Lebowski.
3. The T-shirt worn by Ted reads "highway to hell" in Japanese.
4. Lily admitting to breaking up all of Ted's girlfriends and Ted pressing the line of questioning is a parody of the classic Tom Cruise and Jack Nicholson courtroom exchange in A Few Good Men.
5. The TV behind the group showing Robin's news program has many exciting moments despite the group thinking the show is lame. It starts with Robin holding up a picture of the group and become emotional enough to cry on TV. Other scenes include a coworker being set on fire, the weatherman having a heart attack, etc.

Old King Clancy

1. This episode introduces the running gag of Marshall telling fish jokes.
2. Part of the episode parodies the character introduction sequence in the Guy Richie film Snatch.
3. The last appearance of Bryan Callen as Bilson.
4. Aynsley Bubbico and Aaron Hill were both on the show Greek

Murtaugh

1. At the beginning when Barney is in the laser tag office , every high score on the board behind him says "Stinson"
2. At the end of the scene where Barney accepts the challenge of doing everything on the Murtaugh list, he says "OK chumps, lets do this." He then storms to the bathroom while shouting his own name in a very specific manner. This is a spoof of Leeroy Jenkins, a World of Warcraft (2004) player character. In a player made in-game movie that quickly became very famous within the World of Warcraft community, Leeroy Jenkins is in a team that's in the middle of going through a battle plan for their upcoming whelps fight in Upper Blackrock Spire. Before the leader is finished explaining the plan, Leeroy suddenly interrupts and says "OK chumps, lets do this.". He then proceeds to start the fight by charging head first through a doorway, while shouting his name in the same specific way that Barney shouts his when storming to the bathroom. Leeroy's charge ruins his team's well thought out plan for the battle, killing himself and the rest of his team in the ensuing battle.
3. You can see that Alison Hannigan (Lily) is very visibly pregnant in this episode.
4. In the basketball game, the teenwolf's, the opposing team's best player, number is 23. The same number as Michael Jordan and Lebron James former number. Two of the greatest basketball players in NBA history.

Mosbius Designs

1. You can clearly see that Cobie Smulders is pregnant. In November 2008 Smulders and her boyfriend Taran Killam announced that they are expecting their first child.
2. Alyson Hannigan makes a short appearance in the cold opening and is not again as it was filmed during her last weeks of pregnancy.
3. The punch line to the "What's the difference between peanut butter and jam" joke is in fact a very crude one. However there is a more child friendly version which is, "You can't peanut butter your finger in a car door!"
4. Ted tells Robin the story of the architect who designs a sinking library. Ted explains that the architect was either too proud or arrogant and makes the mistake of not taking the weight of the books into account, which causes the library to slowly sink into the ground year after year. This story is a common urban legend, and there has never been a library sinking due to the weight of the books in it (although there have been libraries that have sunk due to other reasons).
5. After Barney tells Lily the dirty joke Ted says,"And we didn't see Lily again for 4 weeks." In real life Alyson Hannigan wasn't on set for 4 weeks after that due to giving birth to her first child.
6. When Robin sleeps with PJ, he says he is at the Empire State Building. A reference to How I Met Your Mother: First Time in New York (2006) where Lilly and Marshall compare having sex to visiting the Empire State Building.
7. When Marshall describes Jenkins in the episode "Jenkins," the coworker they envision is actually Marcus Denesco who we see in this episode as "Food Guy".

The Three Days Rule

1. Alyson Hannigan could not attend this episode and the following one due to her giving birth to her first child. This makes her the only member of the main cast from the first 8 seasons not present in every episode of the series.
2. The girl Ted is pursuing is named Holli. The restaurant Marshall gets take out from is Generro's. "Holli Gennaro" is the name of John McClane's wife in Die Hard. The movie is referenced several times throughout the series.
3. While texting, a reference is made to a poem by Pablo Neruda. The poem cited is titled "And Because Love Battles". Pablo Neruda is also the poet whose book was found in How I Met Your Mother: The Naked Man (2008).
4. While texting, Stan feeds Barney and Marshall romantic lines from a Pablo Neruda poem. Throughout the series Ted repeatedly states that Pablo Neruda is his favorite poet.
5. Barney mentions girls whose names end in "ly" being dirty. Among the names he list is "Carly." In season 8 episode 14 "Ring Up," we find out this is the name of Barney's half-sister (who he was unaware of at the time).

Right Place Right Time

1. In this episode Robin had food poisoning and Barney and Ted made fun of her saying she's pregnant because she vomited. In real life, the actress, Cobie Smulders who played Robin was actually pregnant at that time.
2. Marshall's Venn diagram with Cecilia at the intersection of the two circles is a reference to the lyrics of the Simon and Garfunkel song, "Cecilia". The opening lines of this song are, "Cecilia, you're breaking my heart / you're shaking my confidence daily..."
3. When Marshall presents his pie chart of his favorite bars, the bar that is in second place is called McGee's, the real life New York City bar McClaren's is based on.
4. Milt, the homeless guy, actually does the correct math on the amount of years it would take for Ted to give him a dollar a day for a million days. As it would be just over 2,739 years.
5. According to his bar graph, Marshall's favorite pie is 'super-righteously tasty'.
6. In figuring out Barney's success ratio with women, Marshall mentions that he has been sexually active for 16 years. We learnt in a previous episode "How I Met Your Mother: The Yips (2007)" that Barney lost his virginity at 23, which would make him 39 in this episode.
7. Lilly does not appear in the epsiode, despite flashbacks, as Alyson Hannigan was on maternity leave
8. Lily, despite credited, doesn't appear in this episode.
9. Barney says for Babe Ruth not to hit too many "homers". The homeless man is played by Dan Castellaneta who voices Homer Simpson

As Fast as She Can

1. Ted has Robin's song "Let's go to the mall" as his ringtone.
2. Alyson Hannigan (Lily) makes a brief appearance at the end of this episode, but is still clearly pregnant with her first child, despite the loose dress and the attempt to hide her midriff behind a very large purse/bag.
3. The character name Richard Greenleaf is an allusion to the character Dickie Greenleaf in The Talented Mr. Ripley (1999).
4. When Stella and Ted are arguing in the hall, Ted's phone rings. His ringtone, "Lets Go to the Mall", was performed by Robin as a teenager. Her name was Robin Sparkles.
5. Alyson Hannigan makes a brief appearance in this episode after having just given birth to her first child, born March 24, 2009.
6. The first time Barney recounts the story of getting pulled over by a female cop, he winks with his right eye. The second time, he uses his left.
7. They make a joke about a new French Stella, Sarah Chalke speaks French and German

The Leap

1. In a flashback where we see Marshall's many attempts of jumping across the buildings, we see him dressed as Dracula during the Halloween segment. Jason Segel is a huge fan of Dracula and once tried to write a Dracula musical involving just puppets. The idea was incorporated into his movie, Forgetting Sarah Marshall (2008).
2. One of the scenes with Marshall on the roof saying was previously used in the episode Three Days of Snow when future Ted gave his list of five words every man eventually says.
3. The song that plays when Missy the Goat and Ted wrestle is "Murder Train" by The Foreskins, featured in Season 3, How I Met Your Mother: Sandcastles in the Sand (2008).
4. Alyson Hannigan had just given birth to her first child (born March 24, 2009)- despite previous claims that she was still pregnant in this episode (a stomach does not snap back that quickly post pregnancy which is why she still appeared pregnant). This episode marks her first full return to the series, after having made a brief appearance in the previous episode.
5. This episode had been shot earlier, out of sequence, because Alyson Hannigan was still pregnant (baby born in March that year) & Cobie Smulders is barely showing at this point (baby born in May that year & would have been very pregnant, if filmed in order). They knew Lily would be on maternity leave in episodes towards the end of the season, hence filming this season finale earlier.
6. During one of Marshall's jump attempt flashbacks it is Halloween and a woman can be seen dressed as what might be considered a Slutty Pumpkin. This references the first season episode "Slutty Pumpkin".
7. At the time of filming, Alyson Hannigan (Lily) is pregnant in real life. The camera angles strategically hide her belly throughout the episode. In the final jumping scene, they DO show Lily's belly (while she is jumping in the air) but not her face, indicating that a stunt double was used for this shot. When she lands her back is to the viewer, and when Ted lands Robin stands in front of her to cover her up.
8. At the time this episode first aired, Evel Knievel had been dead for almost 1.5 years.