this one actually is my favorite quote. but i guess you already know this one if you read it.
"Spaghetti?! That's Italian, you moron! Dammit! You idiots have been in this class for almost the whole school year, and the only Spanish you know is what you learned at Taco Bell! And Beavis can't even get THAT right! I'm going to give you little bastards just 10 seconds to come up with a sentence in Spanish, and if you can't, you're both going to the principal's office, and you're both flunking! Well, I'm waiting!" -from beavis and butthead
"whoa whoa whoa! double straw!? first one free, you're paying for that second one." -from flip's
Sgt. Crapgame: "Hey, Oddball - this is your moment of glory, and you're chickening out." Oddball: "To a New Yorker like you, a hero is some type of weird sandwich - not some nut who takes on three Tigers!"
Anything from No-Bark Noonan from Fallout: New Vegas. Some bangers include:
"We got a chupacabra with an automatic weapon."
"Camouflage, that coat was, trying to hide from extraterrestrials what can only see in black and white checkers."
"Molerat men, come up from the underneath to steal young women with promises of riches and fancy mud mansions with all the latest designer appliances."