Penny: Come on, let's just get this over with.
Leonard: "Let's just get this over with?" Am I driving you to the Cheesecake Factory or are we having sex?

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.

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

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.

Bernadette: Raj, your tag's sticking out. *Bernadette tucks Raj's clothing tag back in*
Raj: Thank you. That's the closest I've come to sex in like two years.
Bernadette: Now I feel a little gross.
Raj: You're only making it seem more real for me.

Sheldon: I have one question. Is this a prank? Where you land in Houston and you've made up wanted posters which have my face with a moustache and a Spanish name, and I get arrested and deported to South America?
Howard: No.
Sheldon: Well I'm glad, because I would not have seen that coming.

Howard: Listen, I was thinking you and I could probably try to be better friends.
Sheldon: Really? I was thinking what we have now is a bit much.