"I see you filled my seathole", "her?!" and "it's as Ann as the nose on plain's face" are my top three.
There are many, many others!
I miss this show :(

"I've made a huge mistake."

"I am having a love affair with this ice cream sandwich." or "Take it back. If I wanted something your thumb touched, I'd eat the inside of your ear."

"I don't understand the question and I wont respond to it."

Lucille- He has been so Moopy. Michael- Maybe it's the fact that a seal ate his Hand. Lucille- I don't know what it is.

Gob: Michael, if I make this comeback, I’ll buy you a hundred George Michaels that you can teach to drive!
Michael: You're losing blood aren't you.
Gob: Probably, my socks are wet.

Buster: It's like she gets off by being withholding.
Gob: Look whose got something to say.
Buster: I'm Mom and I want to shoot down everything you say so I can feel good about myself. 'Cause I'm an uptight BLEEP BLEEP, Buster! You old horny slut!
Michael: Well, no one's gonna top that.

brokenbrain, everytime Lucille says that, I die of laughter! It's hilarious!

I also love:

Buster: Uh, I’m unclear about what it is exactly you do.
Jessie: Excellent question. What a publicist does...
Buster: No, no, I was talking to George Michael. When did you get a job?
George Michael: ...At the banana stand.
Buster: Oh, duh. I thought you meant, like, a plumber or something, and I was, like, when did that happen?

Narrator: Tobias listens to a day's worth of his own words, to see what Michael was referring to...
Tobias Fünke: [on tape] ... even if it means me taking a chubby, I will suck it up.
Tobias Fünke: Nothing wrong with that.
Tobias Fünke: [on tape] Oh, I've been in the film business for a while, but I just can't seem to get one in the can.
Tobias Fünke: It's out of context.
Tobias Fünke: [on tape] I wouldn't mind kissing that man between the cheeks, so to speak.
Narrator: ...and he realized there is something distinct about the way he speaks.
Tobias Fünke: Tobias, you blowhard!

Gob: My gut is telling me no, but my gut is also very hungry.

Also, right after Gob walks into the door at the pet store: What's your return policy?

One more: (Buster cracks the skull at the archeological dig) ...That was 90% gravity.

one of the best jokes ever:

Michael (to GOB): get rid of the Seaward

Lucille: I'll leave when I'm good and ready


also when Michael told his mother to go to the cabin-

Lucille: Oh, how am I supposed to get anyone to go into that musty old clap-trap?

(pause)

Michael: oh, the cabin!

when tobias comes out of the changing room wearing a speedo over his cutoffs...
"Excuse me, do these effectively hide my thunder?"

OR

when michael is talking to his family...
"I got a job...You know, something you apply for and they pay you to... Never mind, I don't want to ruin the surprise."

genius.