Leonard: You know what? I've gone 12 times. Maybe I'll sit out this year, too.
Penny: Really?
Leonard: Yeah. Maybe you and I can do something fun that weekend.
Penny: Ooh, how about white-water rafting?
Leonard: Oh, how about we compromise and go on the Small World ride at Disneyland?

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: 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.

Leonard: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Penny: So, do you want to come?
Amy: No, thanks. I already live in a place all the nerds come to.

Raj: Oh, Double Stuf Oreos, I remember when I could afford you.

Sheldon: He also has a remarkable amount of credit card debt.
Howard: I thought your dad paid your cards.
Raj: I have a card for emergencies that I pay for myself.
Sheldon: What emergency happened at the L.A. Zoo?
Raj: That's a penguin I sponsor. They're losing their homes to global warming, and my car gets, like, seven miles a gallon, so I felt bad.