Penny: Honey, you don't have to thank me every time we have sex, sweetie.

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?

Leonard: I've always been a little confused about this. Why don't Hindus eat beef?
Raj: We believe cows are gods.
Sheldon: Not technically. In Hinduism, cattle are thought to be like God.
Raj: Do not tell me about my own culture, Sheldon! In the mood I'm in, I'll take you out, I swear to cow!

Sheldon: There's a fine line between wrong and visionary. Unfortunately, you have to be a visionary to see it.

Rajesh: Okay, please don't take this the wrong way, but I'd rather swim buck naked across the Ganges with a paper cut on my nipple and die a slow agonizing death from a viral infection, than work with you.