Leonard: Okay, Sheldon, I understand that youre going through a bit of a career crisis, you're searching for some other area where you can feel valuable and productive but I need to tell you something and I want you to listen carefully.
Sheldon: All right.
Leonard: Go away!

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.

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.

Raj: Can you believe it! He watched me work for 10 minutes and than he tried to build a little piece of software that could replace me.
Leonard: Is that really possible?
Raj: As it turned out, yes.

Sheldon: Engineering. Where the noble semiskilled laborers execute the vision of those who think and dream. Hello, Oompa-Loompas of science.

Sheldon: Today, I went from being Wolfgang Amadeus Mozart, to... You know, that other guy.
Howard: Antonio Salieri?
Sheldon: Oh God, now even you're smarter than me.