A bunch of YouTubevideos about a gamer named Kilplix and his friends. These started as montages from Battlefield 2 matches, but when Kilplix started posting footage from his buddies' Left 4 Dead sessions things really took off. Even though his videos are simply a bunch of friends slaughtering zombies (and each other), they've gained hundreds of thousands of views due to the hilarity that ensues and the personalities of the players, who are:
Kilplix (Austin): The leader, and the one who posts the videos. Usually the most rational and level-headed of the group (though this isn't saying much). Plays as Zoey/RochelleZoey.
JedediahJ (Jed): Kilplix's good friend and resident smartass. Though capable, he tends to wander off and get nabbed by Special Infected. Plays as Bill/The Coach!
Sariix (Cody): Jed's brother, and typically a quiet, cool and dependable teammate. Plays as Louis/Ellis.
Buttmonkey: Con's gung-ho attitude and sub-par internet connection mean that he usually dies the most, and during the Left 4 Dead 2 playthrough he only survived one campaign. It doesn't faze him.
Bullet Time: Used to show how, for example, Con managed to hurl a gas tank directly into Kilplix's stream of fire.
The Casanova: Con will hit on anything female, from Zoey to Witches to generic female Infected. This prompts a discussion over it not technically counting as necrophilia.
Cherry Tapping: Adding insult to injury during one night of FAIL is getting bitch-slapped to death by a Boomer.
Clown Car Base: Kilplix tends to get jumped by hordes spawning in small rooms the most, though one time it happened to Con and left him whimpering and huddling in a corner.
Dirty Coward: Jed has the ability to disappear during critical swarms, only later emerging from a closet once the dust has settled. In at least one case this saved him from a Tank.
Five-Man Band: Kilplix and his friends, if you haven't noticed already. It's a shame Left 4 Dead has a 4-man limit.
Freak Out: Jed's response to getting cornered by a Tank or attacked by a Witch is often a stream of high-speed, panicked babbling. Then there's his reaction to learning who dies in "The Passing."
Friendly Sniper: Cody qualifies due to his somewhat gentle demeanor compared to the rest, as well as his penchant for picking up Hunting Rifles.
Gosh Dang It to Heck!: Kilplix doesn't swear. He'll post Gore Montages and admire zombie damage that makes Con squeamish, but he keeps his commentary strictly PG.
He's been starting to avert this lately however. Though it's just been minor, with "piss" as far as it's gone.
Hoist by His Own Petard: Con's boast of being "The Flame Master" aside, he does have a habit of getting too close to admire his handiwork.
Similarly, in the initial L4d2 playthroughs, Jed goes into a safehouse and shuts the door behind him. There is a hunter in there. Hilarity Ensues.
While he and Jed and Cody are taking shelter from a Tank in a treehouse, Kilplix taunts Jonna with "no girls allowed!" Immediately...
Let's Get Dangerous: If Con yells "It's on!" then a) the team is being pressed hard and he's about to start fighting with even less restraint than usual, or b) he's had one friendly fire incident too many and is after payback.
Metaphorgotten: Jed's description of his teammate. "Con is kinda like an M&M at the bottom of a bottle of Pepsi. It doesn't fizz, and it doesn't sizzle, it's just a bottle of chocolate Pepsi... that melts in your hand. You know, it's not edible, but it's kinda cool."
No Party Like a Donner Party: When the entire group ends up stuck in a hole, Jed (playing as Coach) informs them that as the fattest one, he'll try to eat the others, so they'd better shoot him first.
One-Man Army: During one Typical Night of FAIL after repeated TPKs, Jed got fed up, ran off, and somehow completed the level on his own. In The Parish campaign Con once got separated from the group and held out not only against a Horde, but three Special Infected (the others didn't believe him until they saw the corpses). And then there's the Kilplix Killing Sprees from the Battlefield: Bad Company 2 videos.
The Quiet One: Cody, to the point of sometimes not calling out if he is grabbed by a Special Infected.
Screams Like a Little Girl: All of the boys, really, though so far only Kilplix has inspired tribute videos cataloging his shrieks of terror. Oddly enough, Jonna rarely if ever screams.
Cody: Remember, you only have to run faster than the slowest person.
Kilplix: (limping, a floor behind, and closely pursued by a Tank) I HATE YOU ALL!!!
Stupid Sacrifice: Poor coordination for the second The Sacrifice playthrough leads to Kilplix and Cody jumping off the bridge simultaneously.
Teeth-Clenched Teamwork: Just because everyone's friends doesn't mean that the gaming sessions go smoothly. Particularly evident in the "Typical Night of FAIL" videos.
Jed: Con took down half the team back there.
Con: And half the zombies!
Jed: ...But half the team.
Con: Well, you know, you take some, you give some, you kind of shoot some, what can you do?
Tempting Fate: Kilplix a few times. "You ever notice how a horde never attacks... here..." (rising chorus of snarls) "Okay, I shouldn't have said that."
"They're not gonna spawn YAAAAAAAHHHHH!!!"
When they can hear a tank somewhere nearby, but can't see him yet:
Kilplix: Do not seek him ou-(slow-mo scream when Tank drops down right in front of them)
Too Dumb to Live: Whether it's misuse of explosives, lethal cases of Attention Deficit Disorder, or a poor choice in escape routes, everyone will have their moments.
Con: (posthumously) I wasn't sure if it was a water bottle or a gas tank... so I shot it.
Web Comic: A very minor one, The Misadventures of Kilplix N Friends.