Penny: You know, just-just one thing. Look, we're in a really great place right now, and I don't want to do anything that will make stuff all weird again.
Leonard: So we won't let it get weird.
Penny: Okay. Oh, and just a heads-up, mm, since the last time you saw me naked, I got a Cookie Monster tattoo. The acceptable responses when you see it are awesome or nothing.
Leonard: What about ... (in a low voice) Cookies!

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.

Mr. Rostenkowski: Walnut?
Howard: No, thank you. I'm allergic.
Mr. Rostenkowski: Oh, sure. My partner used to have that. He's dead now.
Howard: From nuts?
Mr. Rostenkowski: Nah, his wife shot him. But she was nuts, so in a way.

Mr. Rostenkowski: It's gonna be okay, son.
Howard: You really think so?
Mr. Rostenkowski: Of course. A pretty girl like Bernadette, she'll find a new guy.

Amy: We're playing doctor. Star Trek style.