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?

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

Penny: At one point, they had me figure out how to get a banana out of a puzzle box.
Leonard: Wait, Sheldon gave me a banana in a box. He was testing me, too.
Penny: Unbelievable.
Leonard: And how could a chimp even solve that? That was impossible.
Penny: Really? You couldn't get it out?

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

Howard: Oh, man. This is the boutineer from my high school prom. A piece of cake from my Bar Mitzvah.
Bernadette: Did she throw anything away?
Howard: No. If I find my foreskin, I'm gonna kill myself.

Howard: All Ma's food is going to be ruined.
Bernadette: Why don't we take it home and put it on our freezer?
Raj: You don't want to do that. Refreezing not only removes moisture, but it creates ice crystals in the fibres of the meat that can compromise its taste and texture. What? I saw a teachable moment. I dropped some culinary science.

Sheldon: Is it my fault I have a much bigger reputation than he does?
Amy: It's not your fault.
Sheldon: Is it my fault that my name came first on the paper alphabetically?
Amy: Not your fault.
Sheldon: Is it my fault that when the reporter cited me as the lead scientist, I didn't correct him?
Amy: Hey look at that pretty bird.