Leonard: Why do I always have to carry the heavy stuff?
Sheldon: Well, it's very simple. In our ragtag of scientists with nothing to lose, I'm the smart one, Wolowitz is the funny one, and Koothrappali is the lovable foreigner who struggles to understand our ways and fails, and that leaves you, by default, as the muscle.
Leonard: One more floor, and I'd be the pulled muscle.

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: One ring to rule them all.
Rajesh: One ring to find them.
Wolowitz: One ring to bring them all.
Leonard: And in the darkness bind them.
Rajesh: Holy crap are we nerdy!

Sheldon: So, just to clarify, when you say three, do we stand up or do we pee?

Leonard: What was that?
Penny: Sheldon tried to steal the ring so I punched him.
Leonard: That's my girl!