Marge, can I have a moment alone with the sandwich?

Go banana!

"I'm tired of being a wannabe league bowler. I wanna be a league bowler."

"Give me the…..thing……that…..you dig…..food…..with."

First of the month! New billboard day!

"I've sold monorails to Brockway, Ogdenville, and North Haverbrook, and by gum, it put them on the map."

He repeats it in an abbreviated form later: "Not back; avenge death"

I use this frequently whenever referencing my domestic inferiority…
Homer: "There's the right way, the wrong way, and then there's the HOMER way."
Bart (or Lisa?): "Dad, isn't that just the wrong way?"
Homer: "Yeah, but it's faster." The matter-of-factness with which he delivers "faster" makes the joke.

Also, the repeated sound, as the credits roll, of startled falling as people reach the top of Springfield's escalator to nowhere.

Also from that episode I believe…
Kent Brockman: "Even though the only bridge out of Springfield was blown up by the rocket, people continue to attempt to cross; a true testament to Springfield's never-give-up, never-think-things-through attitude."

Apu: "My favorite baseball squadron is the Nye Mets."

Ralph: "What's a battle?"

(Exasperated) "Now Mr. Simpson, when I press down on your foot and say 'HELLO MR. THOMPSON,' you smile and nod. HELLO MR. THOMPSON."
(Pause; Homer stares blankly)
Homer, whispering to the agent next to him, "I think he's talking to you."

Simpsons sound effects:
The nuclear power plant winter retreat, when the entire staff offers a glove-muffled round of applause to Burns' keynote. To this day, that sound of gloved clapping always triggers disproportionate giddiness whenever I hear it.

Must've been that BEAN I had for dinner.

The cat burglar episode:

Lisa: "Wow dad, exactly what you said would happen came true."
Homer: "I know honey, I'm scared too."

I say this line every time we have crappy weather. It consistently baffles people around me.

To obtain a special dialing wand, please mash the keypad.

Holds it…..HOLDS IT……HOLDS IT!!!!!!!!!!!!!!