'"Anders"': It's Ahn-ders! I have an Ahn at the beginning of my name! I have a hard-ahn!
Book Ends: "Teenage Mutant Ninja Roommates" starts and ends with the guys all arguing and yelling at each other at the same time, only to stop and share a few contented bites of food, at the beginning, it's pizza, then at the end, donuts.
In "Straight Up Juggahos", the boys scheme to set Jillian up on a blind date with a man they found online, telling her he is a friend named Jake Heisenripbauer (a name they made up on the spot). At the very end of the episode, Jillian calls him by the said name, leaving us to assume that she's been calling him that the entire time and that she still doesn't know his real name.
"Model Kombat" has Blake meeting a sports shop owner who lost nearly all his sight during the war when a piece of shrapnel hit him, but Blake mistakes his words for "pizza shrapnel." Later in the episode, Adam throws a pizza slice at Ders. Blake immediately yells at him, asking if they have any idea how many people go blind due to pizza shrapnel.
In the cold open of "In the Line of Getting Fired", Adam says that he'd be willing to give head to a man for $900 (which he immediately recants). During the closing scene, Blake is being put into an ambulance after being shot and asks how much it will cost him since he doesn't have insurance. The paramedic says $900. Blake and Ders then tell Adam to put his money where his mouth is.
Butt Monkey: Waymond-he's kind of the maligned sidekick to Montez, in the alternative trio of Montez, Waymond and Jetset.
Really, all three of the main guys. They're shown to be woefully incompetent at almost everything they try.
Catch Phrase: "Tight butthole/loose butthole" definitely comes to mind.
Chekhov's Gun: In the episode "Real Time", while the guys are drinking on the roof in the beginning, Blake is playing with a laser pointer. He later uses it against the future chicks during the bike chase scene.
Continuity Nod: Jillian mentions her cat Brent Hoffman dying in the season two episode "Man Trip". In "Fat Cuz" she tells Adam's fellow cat-loving cousin that it is the anniversary of Brent Hoffman's death.
Another Jillian related one-in "Old man Ders," she mentions that she was adopted by a "horrible Korean family." In "Real Time," she answers the phone by saying 'yoboseyo', which is a Korean greeting.
Delivery Guy: What the three chuckle-heads wind up as during "Orgazmo Birth".
Depending on the Writer: The boys' level of immaturity, Jillian's intelligence, Alice's hostility, etc. often fluctuates between episodes.
Don't Explain the Joke: When the boys pull a "Poop Dollar" prank on someone (they wrap a dollar around poop and then leave it on the ground for someone to pick up or step on), one of them shouts "See we poop in the dollar!" as the victim runs away. When it happens again, they all yell "POOP DOLLAR" as they drive away.
Gorn: The episode "Friendship Anniversary" gets surprisingly violent as the guys kill the rats infesting their house.
In-Series Nickname: "Ders." Anders is hardly ever called by his full name. There are a lot of these, Montez calls himself Monteezy, Blake is called "Uncle Blazer", "Blazer", "Blaze", and "Blazerian". Adam gives himself a lot of nicknames, with fake nickname middle names like "Killzone" "Topgun" and more. For one episode, Ders is called Blonders because he's blond.
Jerk with a Heart of Gold: Alice is indeed a verbally abusive Mean Boss, and in the episode "Model Kombat" she outright tells Adam that she wouldn't care if he died. Later that episode, she saves him from choking to death, and afterwards even grudgingly lets him hug her for a second.
Karma Houdini: The high school kids in "Heist School," who crash the boys' home and party, and decapitate their beloved dragon statue. In the commentary, the guys even state that this was by far the least popular ending of an episode to date.
They encounter the high school kids again in "Fourth and Inches," and they somewhat get even, but even then it's pretty much a Pyrrhic Victory.
Leeroy Jenkins: Adam pulls a Leeroy out of his shroom fueled haze in the first season episode "Office Campout", ruining Blake and Ders' ridiculously childish plan and running straight at who he thinks are burglars, but turn out to just be the tech guys coming into the office to do routine maintenance. He even shouts "Leeroy Jenkins!"
Mean Boss: Alice regularly insults her employees both passively and outright. She manages to avoid being a Bad Boss, since she cares about doing a good job and never fires anyone without cause—she's just a very angry person.
The pilot also features several references to Die Hard, complete with Blake crawling through the vents while paraphrasing a line from the movie.
Again from the pilot, the kid in the playground that the boys try to get clean pee from calls Blake "Hermione".
In the episode 'Temp-tress', Blake gives an impassioned (and poorly delivered) version of the Kurt Russel Speech from Miracle, talking about Montez, including the line 'I am sick of tired of hearing about what a good salesman Montez is.'
In "Real Time" when rollerblading while chugging beers (and already still drunk from the night before), Adam climbs his way over a fence shouting "Kung-Fu!...Hustle!"
In "Timechair", the guys exhange a number of video game shoutouts, comparing themselves to various Mario Kart racers (Blake says he's Yoshi, Adam says he's Bowser, then Wario and Ders is happy to be Luigi), and then Blake says he's a Diddy Kong Racer. Ders says if there's changing games, he's Pierce Bronsan, 007.
"The Promotion" has Adam and Blake pranking Ders by loosening his so that he yanks it out.
Adam: "Oh, what, are you gonna break on through to the other side? Jim Morrison? The Doors?"
Shown Their Work: It's unknown if there are any actual Insane Clown Posse fans on the production staff, but they go surprisingly in-depth into the Juggalo subculture for the episode "Straight Up Juggahos", right down to having one of the Juggalettes dub Adam "Sugar Bear" (the name of Shaggy 2 Dope's character in Big Money Hustlas) in one scene. Sure, they spend most of the episode mockingJuggalos, but at least they got the details right.
The Slacker: Blake, Adam, (and Anders to a lesser extent).
Smart Ball: The guys are depicted as being fairly unintelligent, but in "Teenage Mutant Ninja Roommates" they manage to get themselves out of being stuck in a sewer through teamwork, use of this trope, and Chekhov's Gun.
The Stoner: Though all three of the guys do drugs, Blake is the Most Triumphant Example of this trope.
In The Pilot, a list of over a dozen drugs that are regularly in Blake's system are read aloud; among them include marijuana, birth control, cocaine, meth, and both Dayquil and Nyquil ("Why would anyone take both?")
Unsympathetic Comedy Protagonist: Subverted. While The three main characters are basically the annoying frat boys that come to your party uninvited, get really drunk, and fuck up your couch, they manage to be so inneffectual and pathetic while still showing heart every now and then that they actually become sympathetic.
Vitriolic Best Buds: The three guys all love each other, but they also get really mad at each other very often. Sometimes they go back and forth quickly like in "Timechair" when Ders and Blake get ready to joust. Blake lists off a past grievance of Ders stealing a chick from him, but Ders can't hear him. Blake quickly shrugs it off, saying its in the past, and the two joust with an air of just having (dangerous and reckless, of course).
The Voiceless: Waymond. Enforced-on an episode where Waymond was due to testify in court against the guys, they took action to push the court's affairs back a day, helping to ensure Waymond doesn't speak.
Whole Episode Flashback: The episode "Flashback in the Day" takes place in 2007 and shows how the trio met in college.