Howard: The one thing the William Shatner of theoretical physics needed was an ego boost.

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.

Penny: So what do you say Sheldon, are we your X-men?
Sheldon: No, the X-men were named for the X in Charles Xavier. Since I am Sheldon Cooper, you will be my C-men.

Sheldon: I see. I assume since the rest of you have set the bar so low, you're saving the most impressive contribution for last. Go on Howard, dazzle me.
Howard: Well, my power is the ability to pretend like I give a damn about your piddly-ass problem. And that's 24/7 buddy.

Sheldon: A neutron walks into a bar and asks how much for a drink. The bartender replies "for you, no charge".