Leonard: Uh, let's see. Uh, I am an experimental physicist at Cal-Tech, most of my research is with high-powered lasers, and, oh, I've just gotten a big government grant to see if they can be used to knock out incoming ballistic missiles.
Penny: Wow. Can they?
Leonard: Oh, God, no. The money's pretty good. And I used the equipment to make my own Bat-signal.

Leonard: Penny, as a scientist, my job is to figure out why things happen. But I don't think I'll ever understand how someone like me could get to be with someone like you. You know maybe I don't need to understand it, I just need to be grateful. I love you, Penny.

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.

Bernadette: Boy, I don't know if I could be friends with Howie if we broke up.
Howard: Why not?
Bernadette: I'm a very vengeful person.
Howard: Really?
Bernadette: With access to weaponized smallpox.

Sheldon: I know he (Spock) wouldn't care for an outburst of human emotion, but oh goodie, oh goodie, oh goodie!

Sheldon: And now that I have some wood, I'm going to begin the erection of my settlement.