Campaign ad narrator: Mayor Quimby supports revolving door prisons. Mayor Quimby even released Sideshow Bob, a man twice convicted of attempted murder. Can you trust a man like Mayor Quimby? Vote Sideshow Bob for Mayor.
Homer vs. Patty and Selma - S6-E17
Chief Wiggum: Evening, Simpson. You got a short in your taillight, started blinking when you made that turn.
Smithers: Sir, the actors are here to audition for the part of you.
Mr. Burns: Excellent.
Hannibal Lecter: Excellent. [Snarls].
Mr. Burns: Next.
William Shatner: Ex. Cell. Ent.
Mr. Burns: Next.
Homer: Exactly. Heh heh. D'oh!
Mr. Burns: Next.
Bumblebee Man: ¡Excelente!
Señor Spielbergo: Es muy bueno.
Mr. Burns: Oh, it's hopeless. I'll have to play myself.
[Bart is in class discreetly listening to an incarcerated Sideshow Bob on a talk radio show.]
Birch Barlow: I am going to make it my mission to see that our friend Bob is set free.
Bart: No!
Ms. Krabappel: Well, despite Bart's objections, the people of South Africa can now vote in free democratic elections.
Springfield Connection - S6-E23
Homer: When Marge joined the police academy, I thought it would be fun and exciting, you know, like that movie, "Spaceballs." Instead, it's been dark and depressing, like that movie "Police Academy."
Lisa on Ice - S6-E8
Ralph: Me fail English? That's unpossible!
Jay Sherman: Tonight, we review an aging Charles Bronson in "Death Wish 9."
Charles Bronson: [Bedridden in a hospital.] I wish I was dead.
[Krusty the Clown and Homer dressed up as Krusty are standing next to each other].
Legs: I'm seeing double here. Four Krustys.
Springfield Connection - S6-E23
[Hans Moleman is about to be executed and Homer has eaten his last meal.]
Reverend Lovejoy: Alright Hans, time to go.
Hans Moleman: But he ate my last meal.
Reverend Lovejoy: If that's the worst thing that happens to you today, consider yourself lucky.
Hans Moleman: Are you really allowed to execute people in a local jail?
Reverend Lovejoy: From this point on, no talking.
Flanders: I guess we'll just have to agree to disagree.
Skinner: I don't agree with that.
And Maggie Makes Three - S6-E13
[Maggie is being born.]
Homer: Aw, it's a boy! And WHAT a boy!
Dr Hibbert: That's its umbilical cord. It's a girl.
Homer vs. Patty and Selma - S6-E17
Bart: What a day, eh, Milhouse? The sun is out, birds are singing, bees are trying to have sex with them - as is my understanding.
Answer: I'm not sure if this is the one you're thinking of, but an episode of "Ray Bradbury Theatre," called "A Sound of Thunder," dealt with a similar matter: a group of hunters travel back in time to hunt dinosaurs, only to find things have changed when they get back because someone stepped on a butterfly.
Xofer