Sheldon: I just restocked the old PRK.
Penny: PRK?
Leonard: Public Restroom Kit. Everything a boy needs for making pee-pee in new and strange places.

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.

Amy: Have you made a decision about the TARDIS? I think I can sell it if we call it Big British Portapotty.

Sheldon: Amy, the Daleks are right on my tail. Quick, we need to reset the time circuits. Oh no, I left my Sonic Screwdriver behind.
Amy: Really should have thought this through.

Howard: Come on, one day this may double in value and be worth half what I paid for it!