Penny: Today I drove to Van Nuys for an audition that I thought was for a cat food commercial. Turned out to be porn.
Sheldon: Did you get the part?

Penny: Ooh I thought I smelled pizza.
Sheldon: That's remarkable. If pepperoni were an explosive substance, you could replace German Shepherds at our nation's airports.

Sheldon: She stiffed you?
Penny: I believe that's what he did to her.

Good morning, slut.

Mrs. Cooper, hi, it's Penny. I think I broke your son.

Penny: Let's try some improvisation.
Sheldon: Why not? It seems you're improvising your entire curriculum.

Sweetie, let me put this in a way you'll understand. From the waist down, my shields are up.

You know, for a smart guy you really seem to have a hard time grasping the concept don't piss off the people who handle the things you eat.

Ok, so the same with extra spit on Sheldon's hamburger.

Whatcha doing? Trying to contact your home planet?

Penny: That's thinking ahead.
Sheldon: The alternative would be to think backwards.. and that's just remembering.

Penny: He wasn't intellectually stimulating enough.
Bernadette: Couldn't you just fool around with him and then listen to NPR?
Penny: Wouldn't help. Zack couldn't even spell NPR.

TBBT Quotes

Penny: Here's a question-- as an alien pretending to be human, are you planning to engage in any post-prom mating rituals with Amy?
Sheldon: There are post-prom mating rituals?
Penny: Not always. Unless your date drives a van with an air mattress, then always.
Sheldon: Well, if it's part of the prom experience, then I'm open to it.
Penny: You're kidding.
Sheldon: I may be an alien, but I have urges.If Amy wants to copulate by firing her eggs into space, well, then, I will happily catch them with the reproductive sac on my upper flermin. I'm not the best at reading facial cues, but I can see that you're a little turned on.

Raj: Well, to paraphrase Shakespeare: It's better to have loved and lost than to stay home every night and download increasingly shameful pornography.
Penny: Oh... you poor baby.
Raj: What's wrong with me, Penny?
Penny: Nothing, nothing. You know, if we weren't friends - and you hadn't brought up that creepy pornography story - I'd be on you like the speed of light squared on matter to make energy.
Raj: Hey, you totally got that right. E = MC squared.
Penny: I listen. I have no idea what it means, but I listen.