Two from my favourite one-off characters, Krusty's bank manager, and the Beekeeper:

What kind of catchphrase is that?

"My cat's breath smells like cat food."

"Wait a minute…there's something bothering me about this place…[looks around] I know! This lesbian bar doesn't have a fire exit! Enjoy your death trap, ladies!" [leaves]

Das is not ein boobie!

Hey! There's a lemon behind that rock!

Marge: "Welcome to Pretzel Wagon. May I take your order?"
Lenny: "Uh, let's see. I'll have… one, uh…"
Carl: "Hey, hurry up. I wanna get my pretzel."
Lenny: "One pretzel."
Marge: "Thank you."
Carl: "Uh, let's see, um… I will have… one of your, uh…."
Burns: "Come on, come on, while we're young!"

I believe it was a boaking accident.

Makes me think of that Family Guy episode:
"I want you bigger! It will please me…….."

'Hang in there, baby!' "You said it, kitty!" (looking more closely) 'Copryright 1968.' "Hmm, determined or not, that cat must be long dead. That's kind of a downer…."

(at gunpoint) Yes I am sure. Sure as sure can be.

"Slow down, fatty. You're not on the moon yet!"

Aww…CineCraft hasn't done anything yet. Look at him. He's going to do something and you know it's going to be good!

Simpson, you diabolical…….

His job done, Bender stole everything of value from Robot House and ran off.

That guy and the Beekeeper are my two favourite one off characters.

"Now, we're going to run a few tests. This is a simple lie detector. I'll ask you a few yes or no questions and you just answer truthfully. Do you understand?"

*runs away, starts car, and drives off*

Look at the fine stitching on 'dope'.

Oh, I get it!……….I get jokes.