Sheldon: Before we begin, this may have some unprecedented tax implications. In fact, we should start early 'cause we are gonna be on the phone with the IRS for hours. (gasps) Did anybody else just get goose bumps?
Leonard: Great, so just the three of us.

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: Oh, Stuart, good. I was wondering, will you be accepting Bitcoin?
Stuart: Well, I don't know what that is, but it's got "coin" in it, and my cash register doesn't, so yeah.

Mrs. Wolowitz: Howard, what's going on?! Are you boys roughhousing?!
Howard: No, we're not roughhousing! We're scientists! Scientists don't roughhouse!
Mrs. Wolowitz: Excuse me, Mr. Grown-up!

Mrs. Wolowitz: Howard, I made cookies for you and your little friends!
Howard: They're not my little friends, and we don't want cookies!
Leonard: Actually, a cookie sounds good.
Howard: All right, we'll have cookies! Thank you very much!