Penny: Yo, Raj, talk to me. I'm sorry, just screwing with you.

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Leonard: What am I supposed to do?
Penny: Err, keep your mouth off other women.

Leonard: If I take it off, Sheldon wins.
Penny: Sweetie, every night you don't kill him in his sleep, he wins.

Barry Kripke: Hey, Cooper. I hear you're going to be on the radio with Ira Flatow from Science Friday next week.
Sheldon: Thank you, Kripke, for depriving me of the opportunity to share my news with my friends.
Barry Kripke: My pleasure.
Sheldon: My thanks were not sincere.
Barry Kripke: Ah, but my pleasure is.

Sheldon: What are you talking about?
Leonard: The cultural paradigm in which people have sex after 3 dates.
Sheldon: I see. Now, are we talking date the social interaction or date the dried fruit?

Sheldon: Biologically speaking, Howard is perfectly justified in seeking out the optimum mate for the propagation of his genetic line. Howard: Thank you, Sheldon. Sheldon: And whether that propagation is in the interest of humanity is, of course, an entirely different question.