Penny: So, what are you guys doing?
Howard: Celebrating Columbus Day.
Leonard: We're watching Goonies, Gremlins and Young Sherlock Holmes. ... They were all written by Chris Columbus.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

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.