Raj: Oh, boy, Sheldon's going to freak out.
Leonard: Yeah, he worships Hawking.
Howard: I was actually thinking about bringing him along when I go over there so he can meet the great man.
Raj: That's really nice of you, Howard.
Howard: Hmm, it's no big deal.
Leonard: Boy, a restraining order from Stephen Hawking. It'll look so nice next to the ones he's already got from Leonard Nimoy, Carl Sagan and Stan Lee.

Leonard: What would you be if you were attached to another object by an inclined plane, wrapped helically around an axis?
Sheldon: Screwed?
Leonard: There you go.

Leonard: My point is, while you're spending all this time on your own, building computers or practicing your cello, what you're really doing is becoming interesting. When people finally do notice you, they're gonna find someone a lot cooler than they thought. And for those of you that were popular in high school, it's over, sorry. Thank you. Congratulations.

Leonard: [to a "smiling" Sheldon] We're here to see Koothrappali, not kill Batman.

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?