Leonard: Come here. Tell you a secret?
Penny: What's that?
Leonard: With all these women chasing me, I kind of do feel like Captain Kirk.
Penny: Can I tell you a secret?
Leonard: Sure.
Penny: Keep talking about Captain Kirk, and we're all gonna stop.
Leonard: (impersonating William Shatner) Message received.

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?

Amy: I have a lab full of coked up monkeys with nothing to lose.

Alex: Is there a problem?
Sheldon: Let's not call it a problem. Let's call it an opportunity. To solve a serious problem.

Sheldon: My father used to say that a woman is like an egg salad sandwich on a warm Texas day.
Alex: What?
Sheldon: Full of eggs and only appealing for a short time.