Penny: I finally realize I don't need to be famous or have some big career to be happy.
Leonard: Well what do you need?
Penny: You, you stupid Poptart.

Leonard: If I take it off, Sheldon wins.
Penny: Sweetie, every night you don't kill him in his sleep, he wins.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Bernadette: Maybe we should get one of those machines to help her up the stairs.
Howard: You mean a fork lift?

Leonard: Oh, I know. This might help. *Gets a ring out of his wallet*
Penny: Where did you get a ring?
Leonard: I've had it for a couple of years. Not important. Penny, will you marry me?
Penny: Oh, my God, yes.
Leonard: This would have been so much more romantic if you didn't have monkey hair on your finger.

Bernadette: I'm glad I got that mocha. And you know what else I'm glad about? I bought you a brownie and I ate it in the car!