Penny: All right, this is making me crazy. Somebody's got to go over there.
Leonard: You got feet and legs, you do it.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Amy: I gave you one job! Keep an eye on him. How hard is that?

Sheldon: Because there's only one of me, I'm more valuable.
Penny: Right.
Sheldon: Although, Amy's already taken me out of my package and played with me.

Amy: Why didn't you tell me?
Bernadette: We didn't want you to worry.
Amy: Should I worry?
Penny: No, come on, it's Sheldon. Nothing is gonna happen.
Amy: That's what you said to me when I started dating him. And then five years later, bingo-bango, something happened.