Howard: I'll give your paper to Professor Hawking.
Sheldon: Great, thank you. Oh, that's terrific.
Howard: But in exchange, I'd like you to do a few things for me.
Sheldon: What kinds of things?
Howard: Are you familiar with the 12 labors of Hercules?
Sheldon: Of course.
Howard: You should be so lucky.

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.

Howard: I invented a game. Want to play?
Leonard: Sure.
Howard: It's called Emily or Cinnamon. I give you actual quotes I've heard Raj say, and you guess if he was talking to his girlfriend or his dog.

Bernadette: Does your mother call you every day at work to see if you had a healthy lunch?
Howard: My mother calls me every day at work to see if I had a healthy bowel movement.

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.

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?