Bernadette: Stuart, you didn't have to get us a baby gift.
Stuart: Oh, just homemade coupons for things you might need help with before the baby gets here. Going to the grocery store, driving you to the doctor. If you're not in a hurry, I can dig you a koi pond.
Bernadette: A foot massage?
Stuart: And that's not me being creepy, that's for either of you.

Stuart: Oh, Sheldon, I'm afraid you couldn't be more wrong.
Sheldon: More wrong? Wrong is an absolute state and not subject to gradation.
Stuart: Of course it is. It's a little wrong to say a tomato is a vegetable, it's very wrong to say it's a suspension bridge.

Howard: Hang on, I know a place where you could you stay and earn some money at the same time.
Stuart: Great!
Howard: I just have to warn you: it will involve humiliation, degradation and verbal abuse.
Stuart: So, what's the catch?

Bernadette: Hey, Stuart.
Stuart: *startled* Hey.
Bernadette: Sorry, did I startle you?
Stuart: Yes, but at this point pretty much any customer does.

Sheldon: It's not my fault I'm bad at sharing; I skipped kindergarten.

Sheldon: If it's like your 3-D chess game, then you're out of your length, width and depth. Amy, get the Neosporin, somebody just got burned.

Raj: Hey, this pregnancy had an emotionally-needy third wheel way before you came along.