Sheldon: *knock knock knock* Leonard? *knock knock knock* Leonard? *knock knock knock* Leonard?
Leonard: What, Sheldon!? What, Sheldon!? What, Sheldon!?
Sheldon: Tell me what you see here.
Leonard: The blunt instrument that will be the focus of my murder trial?

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.

Sheldon: I would ask you to find some way to suppress your libido.
Penny: I could think about you.
Sheldon: Whatever works.

Sheldon: Well, this is very pleasant.
Leonard: I'm glad you're enjoying yourself.
Sheldon: And you said there would never be enough pasta for the three of us.

Raj: Ooo.
Penny: What's the matter, Lassie? Did Timmy fall down the well?