A Weighty Aesop: Robin and Barney's relationship has shades of this at one point, though it's mostly about how the relationship is making them unhealthy than it is about how junk food and/or fatty foods are bad for you.
Batman Gambit: The Scuba Diver from Barney's playbook. He anticipated the need for an entire episode as a play
Bilingual Bonus: In the episode "Of Course", the restaurant in the super date is called the Tombeur des Culottes, which translates into The Panty Dropper.
Billy Needs an Organ: Played for Laughs in "Girls vs. Suits". Barney "loses" a suit, but his tailor says he can salvage the buttons to fix other suits. Added some gratuitous faux-drama to their 100th episode.
Broken Record: After Super Bowl 2009: "Or this one?! Or this one?! Or this one?! Or this one?! Or this one?!"
At that upper-crust party in the Alberta: "No. No. No. No. No. No. No."
Canada, Eh?: In the episode "Duel Citizenship", when Robin relapses into her Canadian ways, she goes out drinking with a women's curling team and wakes up in a Toronto hotel room surrounded by hockey jerseys and maple-leaf flags.
Caught on the Jumbotron: The Kiss Cam variation happens to Robin and Brad at a not-really-a-date hockey game, which she attends after she and Barney refuse to define their relationship.
Character Development: Ted comments on how everyone in the gang has changed from Season 1 to Season 5 in the Season 5 finale.
Character Shilling: Two egregious examples, both suspiciously soon after the breakup of Fan-Preferred Couple Barney/Robin. Robin's next Love Interest, Don, was heavily shilled by the rest of the cast (especially Marshall) even before he actually became Robin's boyfriend and despite the fact he seemed to the audience to be an unremarkable Jerkass. Also, when Barney was Flanderised, the rest of the cast suddenly became his enthusiastic cheerleaders of his womanizing, when previous they'd only had a weary tolerance for it.
Chekhov's Gun: Played straight but retroactively: the little yellow bus behind the 2030 Mosby kids.
Very subtly played in "The Window" Maggie's necklace, which she is oftenly seem playing with and her thing for overalls show later that they both reffer to her old crush on the boy next door, Adam, who used overalls and gave her the necklace.
The Chessmaster: Barney's standard tricking girls into sleeping with him aside, The Scuba Diver deserves mention as one damn impressive Gambit Roulette. Not to mention at one point he recorded a video over a porn, knowing that A: If he was ever in a relationship, he would give his porn to Ted, B: He would secretly be unhappy in said relationship, C: Ted would choose THAT porno first, D: That Marshall would be sitting in that particular seat... this was filmed four years in advance.
Childhood Friend Romance: Maggie and her last boyfriend, in what Ted dubs "the second-greatest love story I've ever heard".
Citizenship Marriage: Barney is about ready to propose to Robin under the guise of one of these when they get the news she's about to be deported. Until Marshall lampshades how unrealistic this trope is in the kind of time crunch situation they were facing, the logistics make it an unfeasible and impractical solution.
Cluster F-Bomb: Barney pulls off one of these during a screening of "The wedding bride". 'Censored' to the word "kiss".
Continuity Nod: When Don tries to hook up with Robin he ends up using the Naked Man from season 4, saying he learned it from a blog.
Marshall's song "You Just Got Slapped" from Season 3 is now the jingle for Aldrin Games' "Slap Bet".
Continuity Snarl: In "The Playbook", Robin tells Barney point blank how uncomfortable she is with him hitting on another woman in front of her so soon after their breakup. But when Barney is told in "Of Course" that Robin is taking the breakup hard and that he's been acting like a jerk, he acts so shocked that he throws up in stormtrooper helmet.
Dawson Casting: "Last Cigarette Ever," averts the way HIMYM usually subverts this trope. Typically, flashbacks have the actors playing young versions of themselves, even as teenagers. However, when Present!Marshall goes back to kick his own ass for smoking, they obviously had to get an actor for Jason Segel to wail on.
Robin's early morning show becomes popular because some college kids make up a drinking game about her interviews.
Does This Remind You of Anything?: The Lily / Marshall - Robin / Barney issue is played as a real break up get back together thing. When Marshall and Lily found a new couple to hang out with after Barney and Robin dumped them, it's played as if it was cheating or finding a new love interest way too quickly. It even has a Redemption in the Rain scene
Eek, a Mouse!!: There's also "Home Wreckers", in which a couple of mice run across the floor of the old house Ted just bought... and both Lily and Barney jump backwards into Marshall's arms.
The Eiffel Tower Effect: Averted in "Duel Citizenship" when Robin goes on a bender and Barney tries to dramatically show she'd ended up in Toronto by opening a window hoping to see a memorable Toronto monument except there isn't any.
Embarrassing Slide: At the end of "Robin 101", Ted accidentally presents a picture of drunk Robin to his class in his presentation. That picture is supposed to be for his Robin 101 class with Barney.
Extreme Doormat: Got it, everyone falls in love with Maggie. But why is she unable to reject anyone? Even if she also needs some me time between two relationships, according to Ted.
Fauxshadow: The mother thought Ted was a complete idiot for teaching in the wrong classroom. This was also true of the mother's roommate, Cindy but she is proven in short order to not be the mother.
Feud Episode: Robin to Barney and Ted after they almost screw up her relationship with Don.
Flanderization: After Barney and Robin broke up, Barney not only went back to his womanizing ways, he suddenly became a complete success at it who always scored with each and every girl he hit on (in previous seasons he'd been just as likely to fail as succeed). More episodes centered around Barney's womanizing in mid-Season Five than in the previous four seasons combined. This was mercifully ended in "Of Course", when he finally realizes that all this is painful to Robin and keeps his word to her not to score with his latest would-be conquest. After that, Barney's womanizing went back to the more realistic, just as likely to fail as it was to succeed.
It becomes justified in Season 9 when The Mother suggested to Barney during the flashback where he first met her that this behavior was him overcompensating to escape his feelings of failure when his relationship with Robin ended.
Jerk Jock: Subverted with Robin's date-but-not-really Brad in the season opener. He comes off as cocky and a bit smug, but he's perfectly willing to let Robin be with Barney if that's what she really wants (and offers to let her find out if she likes him, no hard feelings, when she admits she's not sure), and not even retaliating when Barney punched him for kissing her.
Fratbro: Ted is introduced to Cindy when he saves her from a pack of these (one of whom she's nicknamed "Boomer") and confiscates their beer.
Freeze-Frame Bonus: In the scene where everyone is literally carrying their metaphorical baggage, there are a few jokes in there, including "Elvis is alive", and "Still thinks his ska band will take off" – while at least three of the women have "Slept with Barney".
Friends with Benefits: Barney and Robin have this sort of thing going for a while, until Lily forces them to make a choice.
Ted: She's got a backrub and a crumpet, she'll be fine. Relax. Have some fun. Marshall: I just abandoned my wife. How am I supposed to have fun? (4 minutes later, cut to the two jamming to "I'm Gonna Be (500 Miles)" by The Proclaimers)
And in "Zoo or False":
Lily: Baby, you don't have to worry about me. Yes, I'm a little scared, but I'm a New Yorker. I'm not gonna let this change me. (cut to Lily at the shooting gallery with Robin, where she fires) Lily: I've changed! (shoots) I'm a gun person now. (shoots again)
Also, in "The Wedding Bride", after Ted has told Marshall, Lily and Robin about how much he hated The Wedding Bride, the three all claim it looks terrible and that they don't plan on seeing it. Cut to the theater where Lily, Robin and Barney are seeing it (but not Marshall). Future Ted even lampshades it right before it cuts: "Kids, you know where this is going."
Honor Before Reason: When Robin finds out about a Drinking Game based around her interviews, she deliberately says the trigger in order to force everyone playing to drink themselves into oblivion. Ted figures it out and tells everyone to stop playing, but the college kids around him says they have to drink because she said the trigger. Ted joins in the drinking binge anyway.
I'll Be in My Bunk: 1991!Marshall does this when 2009!Marshall shows him a picture of Lily.
Imagine Spot: "Nothing Suits Me Like a Suit" and Barney's interview with Jim Nantz in "Perfect Week".
Informed Ability: "The Wedding Bride" is apparently breaking box office records everywhere, yet it looks worse than something by Seltzer and Friedberg.
It gets worse. In Season 7, Ted's flashback to the first time he said "I love you" to the Mother features them in front of a movie theater featuring "The Wedding Bride III." So apparently it managed to get two sequels.
One must always remember, however, that Future!Ted is hardly an impartial observer here, and thus might be, intentionally or not, distorting the tale.
Intoxication Ensues: Barney at the end of "Hooked" after taking the 'purple pills' the pharmacy girls left behind.
Ironic Echo: both "No-can-do's-ville, baby doll!" and "Can do's-ville, baby doll!"
I Wish You Had Called: Parodied with Lily and Marshall's reaction to Barney and Robin showing up on their doorstep in "The Sexless Innkeeper."
Kick the Dog: Ted's most romantic gestures towards Stella become this in the movie "The Wedding Bride"
Line-of-Sight Name: In another episode, Ted tries to recall the names of his past dates from photographs by associating them with either the occasion ("Bertha" for a girl he met at a birthday party), or something in the picture. He gets them all wrong.
Mary Sue: In-universe, Tony and Stella in "The Wedding Bride".
Mistaken for Gay: Ted, by Don, in "Twin Beds." Robin decides not to dissuade Don from this.
Mood Whiplash: Played for laughs in the season five episode, "The Window."
No Smoking: One fifth season episode revealed that Future Ted has been leaving out the detail that he and the rest of the gang smoked pretty regularly during this period in their lives (this is one of only few episodes that show Robin, Lily or Barney, and the only episode that show Ted or Marshall, actually smoking anything other than sandwiches or celebratory cigars). The reveal is done one by one for the main cast with shocked reactions from the kids in the future each time. The episode ends with Ted detailing exactly when each character ended up quitting for good, in his case it was right after meeting their mother.
Not Now, Kiddo: In the season 5 premiere, the students trying to tell Ted he's teaching the wrong class.
Not So Above It All: The self-help author Anita writes books on how to handle guys properly. But when Barney rejects her in order to spare Robin's feelings, she easily falls for her own trick of playing hard to get.
Oh Crap!: The look on Barney and Ted's faces when Robin catches them in "Robin 101".
Porn Stash: Barney's porn stash makes a second appearance when he gives it to Ted, no longer needing it as he's in a happy relationship.
The Plan: Robin and Barney had ended up having sex every time they tried to talk about where their relationship is going. Lily locked them in Robin's room until they gave her an answer she was happy with (i.e., "boyfriend and girlfriend"). They decide to lie and say they are BF and GF. As they walk off...
Ted:You do realize they were lying, right? Lily:No, Ted... they don't realize they weren't lying.
Barney in the episode "The Playbook": The Scuba Diver
Slut-Shaming: Sometimes played straight, sometimes subverted, sometimes averted.
In the opening episode of the season, averted by Robin and Barney bragging about going on dates with other people despite their kiss at the end of the last season. Subverted when it turns out they were lying so they could maintain a secret relationship.
Subverted when Barney drags Marshall to a strip club. It turns out that Lily is perfectly okay with it and excited by the idea of stripper-Lily. Meanwhile, Robin is thoroughly upset and undercuts Barney's every statement, repeatedly saying she's not okay with it and, "Did one of your whores tell you that?"
The eighth episode focuses on Barney's playbook and is built around shaming him for his rampant sex-games. It also attacks the girls who fall for his tricks, going so far as to state that if they fall for it, they deserve whatever might happen.
Stuck on a Ski Lift: This happens to Barney and Robin. They'd just started having a fight before the ski lift stopped, making their usual strategies for avoiding a fight (Barney leaves the room and/or Robin gets naked) useless.
Talking Your Way Out: In order to get out of receiving the fourth slap, which Marshall had bequeathed to Ted and Robin, Barney attempts to play his two friends off against each other. It doesn't work. Marshall ends up slapping him anyway.
Marshall: Guys, there was no monkey, it was a human being with a gun! Barney: Are you sure it wasn't one monkey standing on another monkey's shoulders wearing a men's trench coat? Ted: It'd be about the right height.
Tough Room: Used as a Running Gag with Robin, whose various jokes and puns are greeting with utter silence. Sometimes averted by the creators, who have said that they can't stand that kind of thing.
And again with Barney, to which hereplies, "If you're not careful, you're gonna lose me."
Unreliable Narrator: Ted doesn't think much of The Wedding Bride knowing it's really about him, yet its breaking box office records and even his friends admit that they really like it. Is it really that bad, or is Ted just so sour over it that he paints it as Ed Wood fare in his stories?