Sheldon: Now, Penny, we don't consume alcohol during Dungeons and Dragons. It impairs our judgment.
Penny: Oh, this isn't alcohol. It's a magic potion that makes me like you.
Leonard: Double potion, please.

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.

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

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.

Sheldon: I've never played Dungeons and Dragons with girls.
Penny: It's okay, honey, no one has.

Howard: A satanic fungus that looks suspiciously like Al Pacino rises from the forest floor and says, (Imitating Al Pacino) "You're playing D&D. You're playing D&D. This whole apartment is playing D&D."

Amy: Go away. Sheldon is nibbling on my ... fourteen! Yes!