Leonard: Your George Lucas autograph is really a me autograph.

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: I invented a game. Want to play?
Leonard: Sure.
Howard: It's called Emily or Cinnamon. I give you actual quotes I've heard Raj say, and you guess if he was talking to his girlfriend or his dog.

Penny: I love him, but if he's broken, let's not get a new one.

Penny: Shouldn't you be getting ready for work?
Sheldon: I'm not going. Would you like to know why?
Penny: You're sad about not getting any thing done last night, so you're gonna sit around and pout about it.
Sheldon: Boy, I'm not nearly as mysterious as I think I am.