Leonard: Why can't he have a desk, Sheldon?
Sheldon: Oh, Lord, will this day never end? As I've explained repeatedly to Dr. Koothrappali, whose ability to comprehend the American idiom fails him when it's convenient, there's absolutely no money in my budget for additional office furniture.
Raj: Oh, but there's money for a drawer full of Red Vines, a marshmallow shooting rifle, and a super executive ant farm with glow-in-the-dark sand?
Sheldon: Yes.

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.

Leonard: Sometimes your movements are so lifelike I forget you are not a real boy.

Raj: Oh, you're so arrogant. If you were a super hero your name would be Captain Arrogant. And do you know what your super power would be? Arrogance.

Sheldon: Oh, Penny. Penny.
Penny: What's up?
Sheldon: Nothing. I just wanted to make Raj stop talking.