Howard: Sheldon, you're a condescending jerk. Why on earth would I want to do something nice for you?
Sheldon: To go to Jewish heaven.
Howard: Jews don't have heaven.
Sheldon: To avoid Jewish hell?
Howard: Have you met my mother? I live in Jewish hell.

Howard: You know, I'm really glad you decided to learn Mandarin.
Sheldon: Why?
Howard: Once you're fluent, you'll have a billion more people to annoy instead of me.

Sheldon: Sheldon Cooper does not cry.
Howard: That's true, you'd rust.

Josh: So, I have to ask, was the robot sexy?
Howard: It was actually just a mechanical hand.
Josh: 'Cause that's all you need, right?
Howard: You are my brother.

Wolowitz: You don't seem to be understanding the English word no. Maybe a different language will help. Russian: Nyet. Chinese: Bu. Japanese: iie. Klingon: qo. Binary-coded ASCII: 01101110 01101111.
Sheldon: It's actually 01100111.

Mrs. Wolowitz You're right. Who am I kidding? You should have seen me when I was young, Sheldon. The fellas used to line up and bring me boxes of candy. Why did I eat it all? Will you hold me?

Howard: Oh, come on, the man torments me. I'm just letting him have a little taste of his own medicine.
Bernadette: Sheldon doesn't know when he's being mean because the part of his brain that should know is getting a wedgie from the rest of his brain.