How I Met Your Mother/Trivia

"Steve: I was on that island for what seems like eternity!"
 * Acting for Two: The five main lead actors also play their respective doppelgangers.
 * Actor Allusion:
 * Recently featured Barney, played by Neil Patrick Harris, typing up a blog entry—The Doogie Howser, M.D. theme plays while he types. In a later episode he comments that "Child actors were just better in the 80's" (Doogie Howser, M.D. again). In fact, it seems we have a diehard Doogie fan. In a Season 5 episode, NPH shows up in scrubs. The season seven episode "No pressure" has Barney compare Lily and Marshall to preppy kids who stage and bet on hobo fights. NPH was a preppy kid who staged and bet on hobo fights on Boomtown.
 * Another one is with Alyson Hannigan's character. When having cold feet before her marriage, one of the items on the list of experiences to have is a big lesbian experience. Her most famous role is lesbian witch Willow from Buffy the Vampire Slayer. Her favorite name for her baby: Tara (Willow's girlfriend from Buffy).
 * At the end of Ten Sessions, the tattoo removal doctor tells Ted to call her if he ever ends up with a dolphin tattoo on his right ankle, which is coincidentally the tattoo that Alyson Hannigan has in real life.
 * Season 3, "Wait for It": When Ted is making out with Mandy Moore's character at the bar, her song "Nothing That You Are" is playing in the background.
 * Season 3, "Dowisetrepla": Marshall fantasizes about life with his and Lily's future kids. They're playing a Nick Andopolis-style giant drum kit.
 * In "Blitzgiving", Jorge Garcia played a cameo role. At one point someone asks for random numbers and he immediately shouts "4,8,15,16,23,42!" the Arc Numbers from Lost. His character is also cursed with being unlucky (as was his Lost character), and compares said curse with being on an island for eternity.
 * In "The Wedding Bride", the actor who plays Tony in the titular movie is played by the same guy who played a soap actor in "Prescription Passion", House's favorite soap. Both "The Wedding Bride" and "Prescription Passion" have him deliberately hamming it up to eleven.
 * Barney aka Neil Patrick Harris pretends to be Neil Armstrong and spend about a minute one of his women spends going "Neil, Neil, Neil, Neil...Armstrong"
 * Lily has a crush on Mila Kunis. Perhaps she recently saw her in Forgetting Sarah Marshall, written by and starring her husband (Jason Segel).
 * Jason Segel plays Marshall, who has a longtime dream of becoming an environmental lawyer and working to protect the environment. This may or may not be a reference to Segel's character of Mike in the 1999 film SLC Punk!, who leaves Salt Lake City for the University of Notre Dame in order to study botany and (guess what?) save the rain forests.
 * Robin's doppelganger is basically her as a lesbian. Cobie Smulders previously played a lesbian in season two of The L Word.
 * Actor Shared Background:
 * Like Ted, Josh Radnor is from Ohio.
 * Like Robin, Cobie Smulders is from Canada.
 * Dawson Casting:
 * The gang frequently plays their younger selves in flashback sequences, even to when they're teenagers.
 * Done pretty literally when James Van Der Beek guest starred as Robin's old boyfriend and played both his teenage self and his middle-aged self (of course, teenage Robin is also played by Cobie Smulders).
 * Inverted with Robin who is actually a couple of years older than Cobie Smulders is in real life (presumably to shift her being a news anchor out of Improbable Age territory).
 * Lampshaded in one episode, when Barney claims Robin always says she's two years younger than what she really is.
 * Defictionalization: The labor announcement that Ted created for Lily and Marshall is an actual site: https://web.archive.org/web/20140517201956/http://lilysinlabor.com/
 * Full versions of the music videos for both Let's Go to the Mall and Sandcastles in the Sand have been created and both songs are up for purchase on itunes. The Bro Code and The Playbook were also made into actual books. Also, an in-universe example when Robin describes the building Ted designed as "a building in your head that became real."
 * Enforced Method Acting: Jason Segel was not told that the bad news in "Bad News" was until the words came out of Alyson Hannigan's mouth while shooting the final scene (which was just one take). He also improvised the line "I'm not ready for this."
 * Fake American:
 * The implied American Lesbian Robin is played by Canadian Cobie Smulders. In fact, all the gang's doppelgangers sans Barney are played with Fake Nationality (see below).
 * Tony, also presumably American, is played by Canadian Jason Jones.
 * Fake Mixed Race: Dark-skinned Wayne Brady plays white Barney's half-brother.
 * Fake Nationality:
 * People associated with Robin are all played by non-Canadian actors/actresses.
 * Jessica Glitter, Robin's co-star from her Canadian children's television show (although it's never stated directly that she's a Canadian citizen), is played by Nicole Sherzinger, an American who was born in Hawaii and raised in Kentucky.
 * Katie and Genevieve, Robin's sister and mother, are respectively played by American Lucy Hale and British Tracy Ullman.
 * Her ex-boyfriend Simon is played by American James Van Der Beek.
 * All the gang's doppelgangers sans Barney's. For Robin's, see Fake American above.
 * The implied Hispanic Mustache Marshall is played by American Jason Segel.
 * The implied Eastern European Stripper Lily is played by American Alyson Hannigan.
 * Mexican wrestler Ted is played by American Josh Radnor.
 * Bangladeshi Ranjit is played by Iranian Marshall Manesh.
 * Hey, It's That Guy!: "Hey, wasn't that blond guy-?" "Heh, please..." "-Dr. Horrible?"
 * Lily used to be a teenaged witch (with an evil vampire doppelganger) with a penchant for doing things at band camp.
 * Making it doubly funny is how Willow mused whether anyone read Doogie Howser, M.D. fanfic. Weeeeeellllllllllll......
 * Hey, Sarevok/Jolee Bindo is Stan the security guard?
 * Wesley Windham-Pryce is a news reporter? Fred is one of Barney's conquests?
 * Inara as the chick with the crazy eyes. (She's coworkers with Andrew, by the way).
 * While at it Ted's mum (Angela Petrelli) is now married to the Mayor of Sunnydale and I think I saw Harmony in one episode as well. This show is where Joss's characters go to catch up.
 * This probably has something to do with Dr. Horrible and Willow Rosenberg being main cast members.
 * The show's creators are, by their own admission on the DVD commentaries, HUGE Joss Whedon fans.
 * Also, Jonathan is now a minister.
 * Elliot Reid is Ted's laser tattoo removal surgeon, and Britney Spears is her receptionist.
 * Victoria from Twilight was Barney's conquest in "Moving Day"
 * Amber and Ted used to date. And, not for the first time, someone will dump her on her birthday.
 * It turns out she wasn't "effable".
 * He dated Cameron, too.
 * Ted's kids are Justin Russo and Dylan Mayfair.
 * In the second episode, Parker gatecrashes Ted's party—probably scoping the joint. Barney even helpfully shows her the roof.
 * "The Pineapple Incident" OMG! Ted slept with Winnie Cooper! And they had a threeway with Kacey from The Sarah Connor Chronicles.
 * Who is also Laurie from Cougar Town
 * You mean Kim Kelly?
 * Mr. Keaton is Ted's dad.
 * Malcolm's dad/Walter White was Ted's boss.
 * Also, Abe is now inspecting houses.
 * Janice sold Marshall & Lily their apartment.
 * Everyday, Ted gives one dollar to Homer Simpson.
 * Barney sleeps with Parker in the "Purple Giraffe".
 * Robin's little sister is a pretty little liar.
 * Ms. Pilsbury/Charlie was the cute coat check girl at the club in "Okay Awesome".
 * Ted dates Donna Pinciotti.
 * Ted's little sister is Jen? I'm surprised they let her be a police officer in the future, what with the shoplifting and all.
 * Neal Schweiber just saw Bryan Affleck! No, wait, it was just Nick Andopolis.
 * And Robin went out on a date with Bill Haverchuck to prove a point about the Lemon Law.
 * In the episode "Atlantic City", Caroline Julian and Gooch bring up obstacles in the way of Lily and Marshall's quickie wedding, followed by a near-miss ceremony officiated by boat captain Eli.
 * In "Blitzgiving", Hurley shows up as the titular "The Blitz" character (real name: Steve), complete with Actor Allusion / Shout-Out:


 * Even better: the numbers he shouts out for the prank text? 4 8 15 16 23 42
 * Fridge Brilliance: This is actually Ted making a subtle joke to his kids, because having watched Lost he knows his friend Steve looks like the guy who played Hurley.
 * Ted went on the same blind date twice with Valerie.
 * Robin's dad just became Satan!
 * Leland Palmer was Satan?
 * Dr. Quinn teaches law now?
 * Silk Spectre II played Stella in "The Wedding Bride".
 * The Wedding Bride is an interesting example, because the actors of the movie (Jason Lewis, Malin Akerman, and Chris Kattan) were actually supposed to be those actors. Meaning this would've possibly been a Hey, It's That Guy! in-universe as well.
 * Zoey is married to Special Agent Dale Cooper/Trey MacDougal/Orson Hodge?
 * Anyone else freak out when Barney opened his door and Trinity was there?
 * A small one, but with bonus: Pat Crawford Brown does small roles like Ida Greenberg from Desperate Housewives. She's the women on the plane who sat next to Lily in Three days of snow, hearing annoyed to her. Also, she's the woman killed by Bullseye in Daredevil because she was annoying him. On a plane.
 * Mr. Moseby was the loan officer in Dowisetrepla.
 * He was also Buffy's school psychiatrist.
 * And Hooch. Hooch is crazy.
 * Jiminy Glick is Marshall's New Boss.
 * Robin dates Kutner
 * Alternatively, you'd expect that Kumar would have recognized Neil Patrick Harris.
 * In Season 6, Robbie Amell plays a love interest of Robin's by the name of "Scooby", and is mocked by the main cast for having dog-like tendencies. Interesting, since two of his best known roles are Scooby-Doo movies.
 * Wait wait wait wait wait, hold the phone for just a second. His name was Scooby?
 * Ruth Fisher is Barney's mother.
 * Hey, It's That Voice!: Harvey Fierstein's signature gravelly rasp is used for Lily's "smoking voice".
 * Irony as She Is Cast: Neil Patrick Harris didn't officially come out as gay until a few years into the show (it was sort of an open secret beforehand). This made Barney's aggressive heterosexuality and his issues with his gay brother James even funnier. There is a whole ordeal with Barney opposing James' marriage, not because it would be a gay marriage but he was opposed to marriage in general.
 * Milestone Celebration: "How Your Mother Met Me", dedicated entirely to the mother, is the 200th episode.
 * The Other Darrin: Jai Rodriguez becomes the second actor to play James' life partner Tom.
 * Promoted Fangirl:
 * Youtube ukulele songwriter Tally Deushane, whose filk song about the saintlike patience of Ted's kids was played over the Season 5 series recap.
 * In interviews, Jennifer Morrison has stated she was a huge fan of the show and actively campaigned to get her part.
 * Reality Subtext: Barney's gay brother shows up a month after Neil Patrick Harris came out in real life; the episode deals with him, a lifestyle choice of which Barney disapproves.
 * Although apparently they filmed the episode with Barney's brother the same week that Neil Patrick Harris was outed, making it more of a Reverse Funny Aneurysm.
 * Several months after Lily and Marshall learned they were having their first child, Alyson Hannigan announced she was pregnant with her second child.
 * Short-Lived, Big Impact: Season Three is the shortest season of the show, but it is perhaps the one where the most important premises of the show are introduced, namely the series' most important Arc Symbol (the yellow umbrella), Marshall and Lily's struggle to find a place they can call their own and a glimpse of the integral Love Triangle between Ted, Barney and Robin.
 * Technology Marches On: Subtly pointed out in "Trilogy Time" where the gang watches the original Star Wars trilogy once every three years. Each time they use the most recent video format, VHS, DVD, Blu-Ray, and in a Flash Forward it was completely digital with Marshall trying to use voice commands to play it.
 * Unintentional Period Piece: Given that the series is entirely told via Flash Backs, it's noted that time passes particularly with some of the pop culture references thrown during conversations and the evolution of the characters' cellphones (from the flip phones to PD As to smartphones). Lampshaded at the beginning of "Mystery VS. History", where a flashback in 2005 shows the gang debating about the most popular food in America and then in 2011, the gang are browsing through their smartphones where Robin searched that the most popular food is bread.
 * What Could Have Been:
 * Jennifer Love Hewitt was initially slated to play Robin but backed out because she ultimately chose to appear in Ghost Whisperer. Likewise, Scott Foley was initially slated to play Ted.
 * An episode of The Nerdist revealed that Gillian Jacobs auditioned for Robin. Chris Hardwick also went up for a part.
 * If the show hadn't gotten picked up for a second season, Victoria would have been the mother.
 * Season 8 was intended to be the final season, but when the show was unexpectedly renewed for a ninth season the planned ending (Robin and Barney get married and Ted meets the mother) had to be pushed back.
 * Within two weeks of the episode airing, Carter Bays and Craig Thomas still hadn't decided on the ending of the series, trying to choose between two endings. The alternate ending was on the season DVD release.
 * Word of God:
 * It is never stated in the show, but the creators have confirmed that Carl's last name is MacLaren and that he owns the bar. This is a Shout-Out in and of itself - Carl MacLaren is a member of the HIMYM crew.
 * Marshall once made Ted swear on the names of his unborn children: Luke and Leia.
 * Over half the main cast have worked with Joss Whedon. Alyson Hannigan rose to fame in Buffy the Vampire Slayer, Neil Patrick Harris was in Doctor Horribles Sing Along Blog, and Colbie Smulders is in The Avengers. Jason Seagal and Josh Radnor are the only main cast members who haven't worked with Whedon.
 * One episode shows a picture of Robin appearing on Letterman. In real life around the week later Colbie appeared on that show to talk about her role in the Avengers movie.