Penny: Wow, I can drink a beer underwater!

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?

Penny: [to Raj] Run to India.

Amy: As my mom used to say, "When you're doing a puzzle, it's like you've got a thousand friends." She was full of fun lies like that.

Sheldon: My brain is better than everybody's!