The moment that had me laughing so hard that I thought I would explode a lung was the Boy Scouts episode. I apologize If I butcher this:
Bart is watching Itchy and Scratchy with Homer. Itchy ties Scratchy up in a knot, to which Bart replies with his newfound scouting knowllege that such a knot would never hold. Homer replies that its TV where anything is possible…just as a second Homer casually walks by the window.
That was too damn funny.
Alright I’ve only seen this like twice but here goes, the scene starts out with Homer praying to God and then Marge walks in:
Marge- Homer thats not god thats a pancake stuck to the ceilingprys pancake of ceiling
Homer- Lord I know I shouldnt eat thee but…eats pancake mmmmm…sacrilicious.
Bart: There’s your answer, fishbulb! (after watching the Mr. Sparkle advertisement, which is great in and of itself).
Also:
Sexy man trying to seduce Marge: I want to take you out… to brunch.
Marge: Hm, what’s that?
SMTTSM: I think you’ll like it. It’s a little like breakfast, a little like lunch, and comes with a slice of canteloupe at the end.
To avoid duplicating anyone else’s efforts, I usually read to the end of a thread before responding. In this case, I’ll make an exception and reply first, then see if anyone agrees with me.
(Quotes not necessarily verbatim)
Moe: “Who knew Maya Angelou was black?”
Bart: “Actually, I’m quite familiar with the poetry of Pablo Neruda.”
Lisa: “But Dad! Bacon, ham, and pork chops all come from the SAME animal!”
Homer (patronizingly): “Yes, Lisa. A MAGICAL animal!”
“Ooh, they have the internet on computers now!”
(Homer, of course)
I’m going to second that. That’s my favorite episode.
When Homer loses the Best New Artist Grammy to Dexy’s Midnight Runners:
“You haven’t heard the last of them!”
Marge: “We leave you at home with the kids for three hours and the county takes them away?”
Grandpa: “Bitch, bitch, bitch.”
Homer “…alcohol- the cause of, and solution to, all of life’s problems.”
It is hard to narrow it down to a moment, especially when I love every moment of the Cape Feare episode.
I would have to say:
Sideshow Bob: “No it’s German. The Bart The.”
Woman in the courtroom: “No one who speaks German could ever be bad.”
Lisa [upset about the talking Malibu Stacy doll]: Change what she says. It’s your company.
Stacy Lavelle, creator of Malibu Stacy: Not since I was forced out in 1974. They said my way of thinking just wasn’t cost effective.
Lisa: [gasps] That’s awful.
Stacy: Well, that, and I was funneling profits to the Viet Cong.
Wow, is there some sort of secret SDMB requirement for a Simpson’s quote thread at least once per month?
Well, I will add my sig for now.
Troy McClure: ** But for that ending to work, you’d have to ignore all the Simpson DNA evidence. And that would be downright nutty. **
I laughed louder and longer at that line than any other Simpsons live ever!
Actually I think they beat Dexy’s Midnight Runners and won the Grammy. Knowing things about TV does not make me feel smart.
This thread is appropriate with the new season beginning this Sunday.
“There is no air in space!”
“But there’s an Air & Space Museum!”
Yeah, you’re right Lost4Life. I could’ve checked in my Simpsons book but that would’ve been cheating. 
Gosh Euty, this doesn’t even come CLOSE to a Simpsons’ quote. Please read the OP before hijacking it with unnecessary non-Simpsons comments.
Sheesh.
“Marge, if you’re a cop, that makes you “The Man.” And if you’re “The Man,” that makes me the woman - and I’ll have to wear your underwear (which as I’ve said before, is strictly a comfort thing).”
Or words to that effect.
You’d be suprised how often this quote gets thrown around at my house.
Very probably.
“…he’s about to hit a chesnut tree – ah!”
Well then, when in rome. . .
Mexican Millhouse - “Once again I must sugar my own churro”
Smithers - “I don’t think women and seamen mix”
Burns (angrily) - “Yes, we all know what you think!”
Lisa (I’m paraphrasing) - “You know the story of Oedipus. It’s where he kills his father and marries his mother”
Homer - “uggh. Who pays for that wedding?”