Leonard: I'm the king of foreplay.

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: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Leonard: [to a "smiling" Sheldon] We're here to see Koothrappali, not kill Batman.

Howard: Hell hound.
Raj: Who let the satanic dogs out?

Raj: Sheldon, that's my water.
Sheldon: Oh, dear Lord!
Leonard: That's not your water.
Raj: I know.

Priya: What happened?
Bernadette: Howard's mother had a heart attack because I have sex with him and she can't.