Professor Proton: I power a clock with a potato.
Penny: Shut up! You can do that? I mean ... wouldn't that solve the world's energy crisis?
Professor Proton: No.

Professor Proton: Just, just call me Arthur.
Sheldon: Leonard, did you hear that? Professor Proton said I should call him Arthur. That means we're friends. Professor Proton: No, a friend would've told me about the elevator.

Howard: How'd you get him to come to your house?
Sheldon: As Professor Proton always says, there is no problem you can't solve if you use your noggin.
Leonard: And he wrote him a check.
Sheldon: Yeah, that too. A big check.

Raj: I like you a lot, and that's scary for me. Mostly because you're a proven flight risk.

Sheldon: See what happens when you let girls play D & D.

Penny: Oh, it's not so bad. You lost money, you're filled with shame, and you got groped by a stranger. That's Vegas. You nailed it.

Raj: If you wear something brown and sit on the couch, they won't even know you're there.

Sheldon: Leonard, you're being selfish. We need to give you a proper send-off so we'll have closure when you die at sea and crabs eat your face.

Leonard: Sheldon's nervous about me leaving. Just keep an eye on him while I'm gone.
Penny: Oh, I don't know. Remember what happened when I took care of your goldfish?
Leonard: Well, flush Sheldon down the toilet and get me a new one.

Amy: Excuse me, but I'm a neurobiologist. I think I'm a little more qualified to understand what's not working in your girlfriend's brain.

Penny: Oh gosh. Sheldon, the genius, is jealous of Leonard.
Sheldon: I'm not jealous. I'm just very unhappy that good things are happening for him and not happening for me.

Bernadette: You know, one of the things that helped me get through Howard being in space for so long was getting married before he left.
Penny: Bernadette, sweetie, shut up.

Sheldon: It did not kill me when you went to space. Monkeys went to space.

Raj: Okay, I have a request to make.
Amy: And now he can talk. I want to cut open your brain and see what the heck is going on in there.

Amy: Go away. Sheldon is nibbling on my ... fourteen! Yes!