Raj: I'd like to propose a toast to our friend, Howard. His, um, his big heart, his beautiful soul-
Leonard: And his tight little pants that somehow did not make him sterile.

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.

Leonard: [to a "smiling" Sheldon] We're here to see Koothrappali, not kill Batman.

Penny: Oh, it's Leonard. He says Sheldon's drunk and they're gonna do karaoke if we want to join them.
Penny: That sounds fun.
Amy: Oh, no. Sheldon's drunk texting me.
Bernadette: What's it say?
Amy: "Would you like to sing karaoke with us."
Bernadette: How is that a drunk text?
Amy: He used a period instead of a question mark. He's so wasted.

Howard: I love you. And I'm not just saying that because your breasts are gonna get bigger.

Sheldon: You're kidding! What kind of maniacs have coitus in someone else's bedroom?!
Howard: Thank you, Pasadena! Good night!