Leonard: It's the greatest scientific feud of all time. I mean, you can forget about Leibniz and Newton.
Penny: Done.

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

Raj: [to Amy] If you were having Sheldon's baby, would you really want him in the room?
Penny: Yeah, if he's in the room when they're making the baby, I'll give you $10.

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

Howard: Why would the military want Sheldon?
Leonard: I don't know. Target practice?

Barry Kripke: Whoa, whoa, whoa. You didn't tell me we were doing this just to stick it to Sheldon.
Leonard: Well-
Barry Kripke: I messing with you. This sundae just got a cherry on top!

Sheldon: And worse than that, Edison filmed the first on-screen kiss, so he's basically a pornographer. Although every time I put that in Wikipedia, someone takes it out.