Sheldon: Leonard, can you drive me to work?
Leonard: Yeah, sure. Oh, hey, the guys and I were talking about going to see the Tesla coil at the observatory later on, if you want to join.
Sheldon: Oh, I'm sorry, I can't. I'm busy.
Leonard: Why? What are you doing?
Penny: Leonard, what are you doing? He said he can't go. Make a sad face, move on.

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.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

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.