Howard: Sheldon, some day, if you get a car, I'm sure they'll give you another parking space.
Sheldon: I don't want another parking space. I want my parking space. It's perfect. It's a corner spot, cutting the risk of door-dings in half. It's a mere 28 steps from the building entrance. The nearby tree provides shade on hot days and is also home to a delightful squirrel. Which is fortuitous because most squirrels are real jerks.

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.

Bernadette: Gosh, Amy. I'm sensing a little hostility. Is it maybe because like Sheldon's work, your sex life is also theoretical?

Howard: Are you listening to yourself?
Sheldon: I always listen to myself. It's one of the great joys of my life.

Sheldon: You know what they say. Revenge is a dish best served nude.