Raj: You're not going to prison.
Leonard: But, boy, it is funny to think about.

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.

Penny: Hey, since when do you do laundry on a Thursday?
Sheldon: Oh, I had an accident at work, I slipped and fell on my soup sack.
Penny: You know, there was a time I would say "What's a soup sack?" But I'm glad we're past that.

Penny: You know, there was a time I would say "God bless you," and then you would say "If you must invoke an imaginary deity, how about Thor?" And I would say, "How do you know I didn't mean Thor?" And then you would say "Touche," and that there ends the tale of why I no longer say "God bless you."
Sheldon: Well, we have had some fun, haven't we?
Penny: Oh, yeah.

Stuart: Oh, thanks again for letting me use your laptop last night.
Bernadette: No problem.
Stuart: Was just doing my taxes.
Bernadette: Okay.
Stuart: Actually, if I could if I could just check one more-
Bernadette: Already cleared the browser history.
Stuart: You're a good woman.