Raj: Oh, my God, this tomato is amazing! I can eat it like an apple.
Doctor Wolcott: My secret is I fertilize it with my own manure.
Howard: The look on your face.
Leonard: It's a sort of grin. You want to know what kind?

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: 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.

Sheldon: This song is never going to stop. Have you ever dealt with something so relentlessly irritating?
Leonard: That's a trick question, right?

Sheldon: Well, of course I'm worried about you, I want you to be safe.
Amy: And I want you to be safe.
Sheldon: I will be. I'll have my friends with me. If anything should go wrong, I can use them as human shields.

Sheldon: Do you really know how to Riverdance?
Amy: You tell me.
Sheldon: I'm the only man you do that for.

Doctor Wolcott: Well, let me show you around. This is the chair where I do most of my thinking, my thinking about work. Now, my thinking about people who have wronged me, I do over there.
Sheldon: I've always said that I should get a grudge chair. Leonard, have I not always said that?
Leonard: Mm, you have, but you were worried you'd spend too much time in it.
Sheldon: Yeah. That is a real concern.