Sheldon: You know, right now, at the back of this line, there's a movie fan like you who's not going to get in, because this person simply doesn't care. Yeah, well, 61 years ago, there was another person at the back of the line and her name was Rosa Parks.
Leonard: (To Raj) Okay, you may have to pretend you're black to get us out of here.

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.

Stuart: Anyone else need anything before I go?
Howard: I'll give you a dollar if you make fun of Raj.
Stuart: That's mean.
Howard: Five.
Stuart: You look like Tigger if Tigger looked like a jackass.
Howard: Uh, if you ever need a reference or anything, just let me know.

Penny: Helium.
Sheldon: Yes.
Penny: Yes.
Sheldon: Taylor Swift.
Penny: Yes. Pi.
Sheldon: Yes. Kardashian.
Penny: More specific.
Sheldon: Khloe?
Penny: Yes.
Sheldon: See, I remembered because if it looks like Kim it's Kim, if it looks kind of like Kim it's Kourtney, and if it looks nothing like Kim it's Khloe.

Penny: Oh, that's a Venn Diagram, and I remember because I thought to myself, "Venn is he gonna stop talking about this diagram?"