Sheldon: Third barrier passed. You have won the right to see your room. Huzzah!
Leonard: Is this it?
Sheldon: No, this is my room. People don't go in my room.
Leonard: So where do you sleep?
Sheldon: I don't understand.
Leonard: If people don't go in there, and you're people, and… You are people, aren't you? Making a joke.
Sheldon: Do you do this often?
Leonard: On occasion.

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.

Mrs. Wolowitz Howard, are you having a playdate?
Howard: I don't have playdates. I have colleagues.
Mrs. Wolowitz Do their parents know they're here?
Howard: No, but if you keep screaming, maybe they'll hear you.

Sheldon: This is the temperature you agreed to in the roommate agreement.
Leonard: Aw, screw the roommate agreement!
Sheldon: No, you don't screw the roommate agreement. The roommate agreement screws you.

Sheldon: I assure you, you'll be sorry that you wasted your money on an iPod when Microsoft comes out with theirs.
Rajesh: Do you have an opinion about everything?
Sheldon: Yes.
Howard: And you just assume you're right?
Sheldon: It's not an assumption.