Sheldon: Now, down to business. What would it take for you to abandon Leonard and join me in a rival company? Unless, of course, the mugs are sufficient, in which case, welcome aboard.
Howard: We're not quitting on Leonard.
Sheldon: I understand. And your loyalty is admirable. But what if I were to up the ante?
Raj: What are you talking about?
Sheldon: Monogrammed key chains with a built-in laser pointer. No? How about can cosies emblazoned with our university mascot? Go Beavers!
I'll be back.

Raj: I don't like bugs, okay. They freak me out.
Sheldon: Interesting. You're afraid of insects and women. Ladybugs must render you catatonic.

Sheldon: Scissors cuts paper, paper covers rock, rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitates lizard, lizard eats paper, paper disproves Spock, Spock vaporizes rock, and as it always has, rock crushes scissors.

Sheldon: Why are you crying?
Penny: Because I'm stupid.
Sheldon: That's no reason to cry. One cries because one is sad. For example, I cry because others are stupid, and that makes me sad.

Sheldon: I'm not saying that all senior citizens that can't master technology should be publicly flogged. But, if we made an example of one or two it might give the others incentive to try harder.

Raj: Ooh, Leonard is going all alpha nerd on Sheldon's ass.

Leonard: I had a great idea. Do you know how we're always having to stop and solve differential equations, like when you're doing Fourier equations or using the Schroedinger equation?
Sheldon: Howard doesn't, he's only an engineer.