Shout Outs from How I Met Your Mother:
Season One
- In "The Pineapple Incident", Marshall thinks Carl is a vampire. And for a brief second, Lily seems to agree. Lily's actress Alyson Hannigan has appeared as one of the main characters on Buffy the Vampire Slayer.
- "Best Prom Ever" has Lily mention several times she wanted to have a lesbian experience.
- "Game Night": The sequence showing the first time Barney dons a suit is an homage to the scene where Anakin Skywalker dons the Vader suit in ''Star Wars Episode III: Revenge of the Sith.
- "The Slutty Pumpkin" is an adult version of It's the Great Pumpkin, Charlie Brown. The title for one, the Halloween setting, a believer following the same ritual year after year, his friends making fun of him for it, a friend bringing him a blanket late into the night after it's clear the pumpkin's not coming, etc.
Season Two
- The McLaren's bartender gets the entire bar to shout "SWARLEY!" when Barney, er, Swarley walks in at the end of "Swarley", and then starts "Where Everybody Knows Your Name" (the Cheers opening theme) on a boombox. The closing credits use the same font as Cheers.
- In "How Lily Stole Christmas," Ted substitutes Grinch for another word for the sake of his children, telling them: "Only I didn't say grinch." He then follows this up with: "Only I didn't say fudge," just to make the reference more obvious.
- The episode "Arrivederci, Fiero" give a nod to PulpFiction when Lily and Robin spill Thai food all over the inside of Marshall's car.
Season Three
- At the end of "The Bracket", Barney blogs about his experiences while theme music from Doogie Howser, M.D. plays.
- In "Dowisetrepla", Ted describes the scene of Lily and Marshall fighting and finishes with putting his sunglasses on in a very David Caruso way."Lily left the lid off, then Marshall blew his."
Season Four
- In "Do I Know You?", Marshall asks Ted what color Stella's eyes are, and he responds with, "The color of the ocean after a storm", which is paraphrased from The Princess Bride.
- The ending of the episode "The Naked Man" has Ted narrating to the style of Jim Gordon in the Dark Knight flick.
- Barney had repeatedly tried hitting on her to no avail. Well in "Three Days of Snow" when he throws a party for a marching band, he asks "Is the flute section seeing anyone?"
- In "Murtagh" after Barney accepts the challenge to do a list of crazy things in 24 hours to prove he's still young enough, he shouts "BARNEY STINSON" in the exact way that the original Leeroy Jenkins shouted his before recklessly charging into battle.
- In "The Front Porch", when being questioned over breaking up Ted with numerous girlfriends, Lily gets her Colonel Jessup on and imitates the famous scene from A Few Good Men.
- In "The Leap" we get the full story of the goat Lily rescued.
- Marshall's description of "the best burger in New York" is a reference to Antonio Salieri's description of Mozart's music in Amadeus.
- In "Little Minnesota," when Robin is about to beat Marshall's high score on the fishing arcade game, a spectator excitedly says, "We have a possible kill screen coming up!"
- Lethal Weapon: I'm too old for this sh… stuff!" Ted watches the films.
- When Marshall describes how wonderful it feels to sleep in a nightshirt, the accompanying fantasy sequence mimics the dream sequence from The Big Lebowski.
Season Five
- "Slapsgiving 2: Revenge of the Slap" when Lily gets crazy eyes and starts blowing people up (metaphorically, as opposed to DarkWillow).
- Possibly unintentional, "Zoo or False" sees Lily, played by Alyson Hannigan, going as a sexy cat for Halloween, then changing her mind.
- "Girls Versus Suits": The closing choreography from the song "Nothing Suits Me Like a Suit" has shirt-waving dance moves reminiscent of "They Got The Mustard Out" from Buffy's musical episode.
- In "Hooked" Barney laments the passing of the era of hot pharma girls, and speculates (while quite high) that the next hot girl profession may be "intergalactic communications officer on a rocket ship to some distant solar system we can't possibly imagine…"
- Then there was the time a kid was running rampant in Lily's class with a toy horse. She admits that she's a psycho when she reveals that during nap time, she cut off the horse's head and placed it in his bed.
- Dead Poets Society: Oh Captain My Captain!
Season Six
- In "Unfinished", Marshall has an entire elaborate A New Hope analogy for GNB and Ted being like "the guy who built the Death Star". Not designing it with any ventilation shafts and clearly marking all the trash compactors on the detention level…
- In "Baby Talk" when Lily wants to name her daughter Tara.
- "Baby Talk" features one to the Pearl Jam song Jeremy in the form of Lily putting her hands up and shouting "JEREMY! NO!" before being covered in red paint. The soundtrack also "quotes" the song.
- "Blitzgiving":
- Ted mentioned he sang "Twist and shout" at the thanksgiving parade and telling Barney that he's not the Blitz, he's The Bueller
- The episode contains a pair of shout-outs to the Buffy episode "Hush." The curse of the Blitz passes from person to person in the form of a wisp of white smoke leaving their mouths, identical to the effect used in "Hush," and several times the characters spontaneously shout "The Gentlemen!" who were that episode's Monster of the Week. One could be coincidence; two, probably not.
- In "False Positive," Barney buys the most expensive suit known to man, thanks to its diamond pinstripes — it's called "The DiBiase".
- From the episode "Landmarks", Ted's mom briefly appears in Ted's dream holding a spinning top that's actually spinning in her hand. A nod to Inception.
- Steve "The Blitz" is a walking Shout-Out to Lost. His name has the same form as his Lost character, Hugo "Hurley" Reyes. Both characters are chronically unlucky. When asked for random numbers, Steve calls out the Arc Numbers from Lost which "cursed" Hurley (making this one a literal shout out). Finally, he compares the unlucky streak to being on an island for a very long time, which is how Hurley's character arc ultimately ends.
Season Seven
- Lily gets the demon eyes and voice in "The Stinson Missile Crisis", and in ''The Pre-Nup Wil… ehrm, Lil hits the trifecta, clearly invoking Dark Willow as a Mama Bear.
- When the gang attends an underground poker game in "46 Minutes", one of the Russians is seen eating Oreo cookies from a poker chip tray just like Teddy KGB from Rounders.
- In the "Slutty Pumpkin Returns," The Stinger shows Barney separating into his American side (represented as Barney dressed as Apollo Creed) and his Canadian side (represented by Barney dressed as a Dudley Do-Right) and the two begin to fight, directly ripping the fight from Superman III.
- In "The Magician's Code, Part 1," Marshall was drunkenly trying to use an ATM, and the ATM's screen turned into the original The Legend of Zelda briefly.
Season Eight
- As a result of sex deprivation in "Splitsville," Lily imagines a three-way between Robin, Nick and that Danish slut Nadia.
- Ted says "Look, I came here to chew bubblegum and pack boxes and I'm all out of bubblegum" mirroring the iconic "kick ass and chew bubblegum" line from They Live!. He even wears shades like the plot device from that movie.
- In "Ring Up", Barney reads a dream from Ted's journal - Ted has to participate in a school play he had never rehearsed for, and someone takes away his clothes. Willow had a very similar dream in the Buffy season 4 finale.
- In "Bad Crazy," Ted needs to purge his crazy girlfriend from his apartment, saying "This is my house, and I have to defend it."
Season Nine
- In "Rally", when Barney is drunk, one of his incomprehensible mumbles is "Aggle flaggle plabble wumby flappy", the entire dialogue of Trixie, the infant heroine of Mo Willems' children's book Knuffle Bunny.
- In "Vesuvius", the gang watch the sequel to The Wedding Bride, which includes a scene where Marshall Expy Narshall eats a chocolate cake Jed had been saving. In This Is the End, Jason Segal (playing a version of himself) mentions a similar idea as a typical sitcom plot.
- In "The End of the Aisle," Barney's dressing room is decorated with The Last Supper, a significant reference considering that the series ended in the episode after this one.
Unsorted
- In one episode after Barney has accepted a challenge, he strides out of the room before while everybody else stays behind and shouts "Barneeeeeey, Stiiiiinsooooon" as a reference to the Leeroy Jenkins meme. He even uses the same voice!
- Barney (played by former child actor Neil Patrick Harris) saying "Call me crazy, but child actors were way better back in the 80s".
- Lily says in a bar, "We need a drink that can turn subtext into text!" The last half of the sentence is almost word for word what Giles tells Buffy in the episode "Ted".
- Marshall tells Jenkins that if she kidnaps him his family doesn't have any money but his wife has a set of special skills.
- At one point in the song on tedmosbyisajerk.com, Barney-as-Ted is accused of being a Cylon.
- In order to argue against waiting for a sign from the universe, a story of Marshall wanting to leave GNB is brought up, where he is walking down a street. An older model ambulance drives by, as Marshall notices a white sign with a no symbol, and across the street a fire house is for sale. Thinking he knows what the universe wants him to do, he asks someone for a phone, who turns out to be Ernie Hudson, who asks, Who ya gonna call?
- Lily and Marshall move out of New York, and Robin goes to visit them, only to feel like their prisoner. When she wakes up Lily is standing over her like Kathy Bates with a sledgehammer… erm, croquet mallet.
- Barney is named after a heroin dealer in the book version of L.A. Confidential.
- In away, the entire series is either this or heavily inspired by The Wonder Years. They even had the girl who played Winnie Cooper in two episodes.
- Several of the plays in The Playbook, but Weekend At Barney's especially.
- There are references to The Silence of the Lambs in two episodes: one where a lady Barney picks up mentions the movie upon acting apprehensive when he takes her to the back of a truck in an alley, and one referring to the pit in the film where Ted, Robin, Marshall, and Lily imagine throwing into the pit people who have wronged them.
