Leonard: I suppose there are worse ways to spend a Friday night. None come to mind.

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.

Sheldon: You know, in difficult moments like this, I often turn to a force greater than myself.
Amy: Religion?
Sheldon: Star Trek.

Penny: Are you saying that Amy is, oh, what's the scientific word-
Sheldon: Forget science: she's horny.

Amy: Ears and genitalia.
Sheldon: Interesting. Not body parts that usually team up. What about environmental factors. Describe the scene for me?
Amy: I was sitting in a restaurant with Penny and Bernadette drinking water. Carbonated as it was a special occasion. Penny's friend Zack stopped by and said 'hello' and I said 'whoo'.
Sheldon: Who?
Amy: Zack.
Sheldon: Then why did you ask?
Amy: Ask what?
Sheldon: Who?
Amy: Zack.
Sheldon: All right, lets start over. What did you say when Zack walked in?
Amy: 'Whoo'.
Sheldon: Zack.
Amy: Why do you keep saying Zack?
Sheldon: Because you keep saying who?
Amy: I'm not saying 'whoo' now, I said 'whoo' last night.
Sheldon: And the answer is Zack, correct?
Amy: There was no question, I simply said 'whoo'.
Sheldon: All right I think I have enough to go on.