Penny: Did we move at all?
Leonard: Maybe a long the Z axis, but X & Y are looking pretty sad.

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.

Howard: How are the taxes going?
Bernadette: Okay, but you've got a lot of receipts for the Lego store in here.
Howard: Those are business expenses. You can write those off.
Bernadette: A $200 R2-D2 is a business expense?
Howard: Oh, Bernie, you're gonna have to sound a lot more confident when we get audited.

Penny: This is why I've been saying we should keep champagne on ice.
Sheldon: Sarcasm?
Amy: Yes.
Sheldon: That was tricky because when it comes to alcohol, she generally means business.

Sheldon: I'm exceedingly smart. I graduated college at fourteen. While my brother was getting an STD, I was getting a Ph.D. Penicillin can't take this away.