Two Gamers On A Couch is an archetype of the Webcomics medium. Many of the most popular webcomics (and the people who read and write them) have an interest in Video Games, and the two gamers on the couch, playing games and shooting the breeze about whatever crosses their minds, is the purest expression of this fanbase/author background.
Two male friends, frequently Author Avatars of the artist and writer of the series, play computer games and have hijinks, mixing in political ideas and unexplained or explainable phenomena that surround their lives. Hilarity Ensues.
The two roommates/friends will often borrow from the archetype of the Straight Man and Wise Guy: One will be wacky and insane, whose passion for computer games and other aspects of nerd culture will result in stupid, crazy, illegal and (hopefully) amusing repercussions. The second will be more down to earth, calm and intelligent — not above being pulled into the wacky one's schemes, but usually knowing when to pull out. He usually has a stable, "normal" career whereas the wacky one will either be unemployed or painfully incompetent at whatever they do.
Sometimes this is expanded into a Comic Trio, when they are accompanied by one or more characters who provide context, perspective, or episode-specific references. These may range from a Snarky Non-Human Sidekick or a Dungeonmaster's Girlfriend to a Gamer Chick, Nerd Nanny, Robot Buddy, Monster Roommate, a Time Traveller, a character from the franchise being reviewed or any other unexplained supernatural or Sci-Fi element that serves as a plot device and may or may not change on a per-episode basis. Most of these series are set in the "real world" and these fantastical elements are handwaved as really cool.
Love interests as stand-ins for the authors' actual wives or girlfriends (assuming that the author has spoken to a girl in his life) are common as are actual Author Avatars who appear in one-off strips and comment on production or philosophical nonsense.
- Penny Arcade: The flagship Two Gamers On A Couch series. Gabe and Tycho (who switch between crazy and sane depending on the plot) are the gamers. This series is the most politically active, making massive amounts of cash from their comic and related projects; they run a gaming expo and a children's charity on the back of the comic. They publish Spin-Off comics of their comics, have also produced their own computer game, and have been featured as an expansion of a moderately successful collectible card game.
In its later years, Penny Arcade cut out the couch altogether unless the comic actually relates to them playing a game at that moment, and avoids talking heads by having Gabe and Tycho have their game-related conversations while performing some irrelevant Funny Background Event, like picking pumpkins with their kids, eating lunch, emerging from hideous cocoons, carrying out a dead body wrapped in a carpet, or sitting on prison bunks.
- Ctrl+Alt+Del: Wacky guy Ethan and straight man Lucas are roommates. Zeke the Xbot is their wacky Robot Buddy who wants to Kill All Humans. Lilah is the down-to-earth gamer girlfriend of Ethan. Hilarity Ensues. The first strips actually poked fun at this very trope, and tried really hard to avoid it. Today, it's most infamous for it's memetic failure at drama, "Loss," the strip in which Lilah miscarries Ethan's child, which has since become the internet's favorite tasteless joke though various remixes and references.
- Garnet and Gure features Garnet, a buffoonish latter-day gamer and Gure, a painfully emotionless old-schooler.
- Brawl in the Family:
- King Dedede discusses the flaws of Super Smash Bros Brawl to Kirby, who's happily playing the game on the couch. Lampshaded Fridge Logic, how King Dedede is complaining about the game where he made his SSB debut. 
- Comic 357 "Bowling" features Kirby, Diddy Kong, and Adeleine playing Wii Bowling on a couch.
- Rob and Elliot: Elliot is the sane/normal school teacher, Rob is the wacky and over-the-top drama queen. Of course, Elliot is only sane in relation to Rob; one arc revolved around his being Not So Above It All when trying to find a new roommate. Doctor Doom(sday) is their megalomaniac next door neighbour, who frequently gets in trouble with the Justice League. It's more like two guys sharing an apartment, as gaming doesn't actually factor into it, but otherwise it fits the trope.
- Applegeeks: Started off as a TGOAC comic but quickly evolved into a more dramatic model. The wacky hawk (Mad Scientist Superhero) was the crazy one and he had many friends who took on the sane side of the dynamic. After the creation of Eve, the Mac-based andoid, the series changed dramatically into a serious action/drama series, and recently became wacky again. A slightly alternate interpretation involves copious amounts of Unreliable Narrator. The squirrel does talk to him, after all.
- Megatokyo: Like Applegeeks, quickly broke out into a different medium and is now a romance shounen (but not the Dragon Ball kind) manga-style comic.
- VG Cats: The avatars of two cats who "act the part" of characters in different computer and console games — we never actually see the couch, just the two characters inside the game, but it fits the same format. The cats are occasionally seen in the real world, when parodying tabletop games or buying a new videogame.
- Life of Riley: Started as a gag-a-day Life Embellished series about two of the members of the 'Clan Bob' online team, rife with in-jokes and innuendo about their girlfriends, but became an increasingly surreal mix of adventure and religious symbolism, before suddenly vanishing off the face of the 'net.
- Little Gamers: The characters spend a lot of time on the couch.
- Real Life Comics: Gaming is part of the overall geekery of the author's interests. Cast of Characters has fluctuated on the author's real life associations. Usually the Author Avatar is wacky, while his wife is sane — but for some situations, it's reversed.
- Shredded Moose arguably owed everything to Penny Arcade except its sense of humor.
- Spoofed in this Slackerz strip, which parodies the format in general and Ctrl+Alt+Del in particular. Later, it was revisited.
- Draw Write Play references the trope and then cites why they do it better. 
- 2 guys sitting on a sofa holding game controllers. Exactly What It Says on the Tin. Lines are submitted by readers, the pictures are ALWAYS the same. To elaborate, panels with text added to them are divided into first panels, second panels, and third panels. Each time you look at the page, a first panel, a second panel, and a third panel are randomly chosen. And hopefully, the combination is funny. Hopefully.
- Sluggy Freelance was arguably this for its first week of strips, with Torg checking in each day on Riff's computer problems, such as summoning the Devil and the archangel Chuck onto his hard drive, who proceed to get into a Quake death match. The series quickly expanded far beyond this, however. Video games and random conversation between the Heterosexual Life-Partners do still appear in the strip, but are only one aspect of the increasingly bizarre and complex storylines.
- Skin Horse pokes fun at the ubiquity of this trope in an early strip]].
- UG Madness is more Two Gamers At A Table Playing Magic: The Gathering. Basically replace the controllers with a few cards and the TV with the table and you got the idea.
- Cyanide & Happiness parodies the trope.
- Fanboys: Pretty much follows the formula except both of the main characters are equally wacky.
- Sequential Art falls into this at times.
- Suzixemma: Sort of an inversion, as the protagonists are girls and they don't just play videogames. And they have yet to actually sit on their couch... but it's the same basic principle.
- In El Goonish Shive, the NP stories are starting to show shades of this. One NP storyline was called "Gaming Webcomic", with The Rant for the second strip beginning "Oh hey, two characters on a couch talking about video games. Neat!"
- Sweet Bro and Hella Jeff is ostensibly this, as it started life as a direct parody of a generic Two Gamers On A Couch comic posted on the Penny Arcade forums. In practice, while the theme is still definitely there (as far as anyone can tell), it's not quite as focused on gaming - only a small number of episodes make reference to playing games, and the only time Bro and Jeff are actually seen on a couch playing games quickly descends into... something else.
- Slapdash Application of Verbiage's Jennings is eager to avoid this.
- Virtual Shackles: Various strips follow this format, with variations such as the two creators, two video game characters, one of the creators with their wife, etc.
- Ronin Press Comics: Two strips involve two gamers commenting on life and their own stupidity.
- In Savestate the two gamers are brother and sister Kade and Nicole, who also happen to be Australian Shepard dogs.
- This trope has shown up a couple of times in Full Frontal Nerdity (Frank and Lewis being the two most likely to do so), but as the series focuses mostly on the characters' tabletop gaming habits it's rare.
- Dominic And Claire: Played straight in the second story in the Dominic & Claire Funnies. Dominic sits on top of a wall and recounts to Claire an anecdote about being on a baseball team as she stands by the wall to listen.
- Shaun of the Dead starts off with one of the two guys (Shaun) questioning his half of the couch, and throughout the movie, tries to reorganize his life and his relationships... but in the film's final scene, he's back where he's happiest, sitting on the couch playing video games with Ed, who's now a zombie but still able to play TimeSplitters 2.
- The 40-Year-Old Virgin brought the trope to the film, with a good mix of Volleying Insults. In fact, a picture of said gamers, plus the line "You know how I know you're gay?", has become a Memetic Mutation, such that anyone asking the question merely posts the picture.
- Wayne and Garth from Wayne's World, which supplies the top quote.
- Endo and Kobayashi Live! The Latest on Tsundere Villainess Lieselotte starts off with Endo and Kobayashi making live commentaries for a Romance Game as a commentator practice, which is not that different from this trope's setup. At least, before they noticed Prince Siegwald can hear what they say from the other side of the screen.
- MTV Germany's video games show Game One could be considered this as it features two gamers as moderators and the studio even has a couch, they rarely sit on it though.
- Gorillaz short "Game of Death" has 2D and Murdoc on a couch with game controllers, watching Noodle and Russell do karate.
- Houkago Play: With the difference that two gamers are various male/female couples.
Other Web-based Media
- Homestar Runner: Spoofed in the Strong Bad Email "web comic", in which one of the types of web comic Strong Bad riffs on are the kind where "slickly drawn college roommates make nothing but video game inside jokes"; cut to a Penny Arcade-like comic of Strong Bad and Strong Sad doing just that, which trails into them randomly listing the tech specifications of the Playstation 3.
- JonTron (later Danny Sexbang) and Egoraptor's Let's Play series, Game Grumps, is literally two gamers on a couch.
- Same goes for Xiil3gendaryzetsubou who are also literally two gamers on a couch (except for a few solo projects).
- Coconut Buyer's series Video Game Dudes is a Take That! at the gaming webcomic genre in general, with the main target being Ctrl+Alt+Del.
- Two Best Friends Play can be classified as this. "Two Best Sisters Play" adds the couch.
- CouchCouple, a YouTube channel that consists of mostly of Let's Plays and tutorials, pretty much runs on this. Ben being the crazier one of the two, and always searching for secrets, and Jo being a bit calmer, who prefers to do the main quest.
- Video Games Awesome! has been Five Friends On A Couch for a great deal of its run, until other commitments got in the way of getting everyone together on a regular basis."Four Player Friday" still happen frequently, even if it's with more than four people. (Or not on a friday.)
- Yahtzee Croshaw and Gabriel Morton are essentially Two Gamers In Yahtzee's Apartment when they record the Let's Drown Out series of videos—hour-long stream of consciousness recordings of one of the two playing a dull-to-watch or poorly constructed game (or the occasional good game) of times past whilst either critiquing the game, talking about gaming news, or being Vitriolic Best Buds.
- James Rolfe and Mike Matei of the The Angry Video Game Nerd fame make James and Mike Mondays episodes, complete with couch. (The same couch where most AVGN episodes are filmed, in fact.)
- Team Four Star has several of these which star various characters, as well as one series — TFS Plays — which is simply the voice actors being themselves while playing video games.
- Beavis And Butthead had sketches which in practice played this trope, but this was before video games had been broadly popularized. What they did instead was usually watch music videos (which was a medium of choice then...it was The '90s), and give a running color commentary.
- Megas XLR is two gamers on a couch, even if their 'couch' as well as the 'game' is sometimes a giant robot.
- Mordecai and Rigby in most episodes of Regular Show. Their ongoing quest to relax ultimately gets them into some very weird predicaments.