Lines That Get You Every Time?
My name's Runt, but my master calls me Stupid.
Skippy: But Aunt Slappy, those were cartoons, and this is real life!
Slappy: (looks at the audience) Don't tell him, he might crack.
Yakko, Wakko, and Dot: (to the tune of "Mary Had a Little Lamb") L.A. town is falling down
While the ground
We won't let it get us down
Slappy: T'was the day before Christmas, in Winter's deep freeze,
Though in Burbank, L.A. it was ninety degrees
Dot: And I'm Princess Angelina Contessa Louisa Francesca Banana Fana Fo Foo---STOP! WHYCANIGTITBYGDDITRBBITWHYGOTTOSTOPITAAUUUUUGH!!!
Yakko: That's my cute little sister who said that!
Yakko: It's that time again!
Dot: To make fun of the Disney Channel?
(From "Wakko's Wish") Pinky: But Brain, if we were meant to fly, we'd be born with little bags of nuts.
The Brain: Pinky, you are a little bag of nuts.
The Brain: You've left the lens cap of your mind on again.
I also like the second time Yakko tells Dot the story of when she was born, just because of the voice acting and animation. But back in the comedic end of the spectrum, I also have to point to my sig.
Fuzzy-Wuzzy was a bear. Fuzzy-Wuzzy had no hair, so Fuzzy-Wuzzy changed his name to Ed Asner.