I think one of my favorite Carl quotes is not from a show, but from a teaser:
"You think you're gonna live forever, but you won't. Someone'll kill ya. Someone'll kill ya with a knife."
One episode ends with Carls head exploding in mid-conversation. Theres a pause. "Why would he do that?" "Why wouldn't he?" I think the head explosion was all that was in the script, and the dialogue was the teams reaction at the script reading.
I think that was the hardest I have ever laughed at any TV show, ever. I love Master Shake. He's such an unbelievable jerk, to the point where he will actually kill himself simply to f*ck with Meatwad's Ouija video game.
I think my favorite episode has to be the one where Frylock tricks Carl into using the Super Toilet 2000, then rebuilds him out of eyeballs:
Master Shake: [Frylock is about to revive Carl, whose body has been recreated from a mass of eyeballs] What a minute. Before you turn him on - do you think he'll be able to be able to see us?
Frylock: In ways you can only imagine.
Master Shake: But look, I mean - is he going to be able to chase us? 'Cause if I woke up lookin' like that, I would just run towards the nearest living thing and kill it.
A close second has to be the episode where the Plutonians are introduced (Welcome to...this horse's anus!):
Frylock: [on the Plutonian spaceship] Which one of these buttons beams me out of here?
Oglethorpe: Those buttons are red! YOU'LL DESTROY US ALL!
[Frylock presses a button and party music plays while balloons and confetti fall out of the ceiling]
Emory: Alright, party time.
Oglethorpe: Whose birthday is it? Someone gets a spanking!
[Frylock presses some more buttons until Master Shake beams in]
Master Shake: Hey! Happy birthday! Who's the lucky boy?
Frylock: SHAKE! How'd you get in this beam?
Master Shake: Look, that beam came from space. You don't own space, so stop acting like you do!
Frylock: I'm outta here.