Penny: Whatever your secret is, I'm sure it's boring, so I'm not interested.
Leonard: It's not boring at all. You see, in higher order mathematics, there are certain sets of equations that...
Penny: Bored.
Leonard: Satisfied?
Sheldon: Hardly. Consider this unlikely but very plausible scenario. A young woman alone in the big city, her ridiculous dream of becoming an actress lies shattered about her.
Penny: Hey, wait a minute.
Howard: Well, hang on. Let's see where he's going.
Sheldon: Then it hits her. How is she going to survive? I mean, she has no prospects, no marketable skills. And then one day, she meets a group of geniuses and their friend Howard.
Howard: Hey...
Penny: Hang on. Let's see where he's going.

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

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

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

Sheldon: I'm not saying that all senior citizens that can't master technology should be publicly flogged. But, if we made an example of one or two it might give the others incentive to try harder.

Raj: Ooh, Leonard is going all alpha nerd on Sheldon's ass.

Leonard: I had a great idea. Do you know how we're always having to stop and solve differential equations, like when you're doing Fourier equations or using the Schroedinger equation?
Sheldon: Howard doesn't, he's only an engineer.