Wolowitz: I mean, even Donkey Kong had Donkey Kong Jr. so he could teach someone how to kidnap princesses and throw barrels at Italian plumbers.

Howard: You know, I'm really glad you decided to learn Mandarin.
Sheldon: Why?
Howard: Once you're fluent, you'll have a billion more people to annoy instead of me.

Bernadette: Maybe we should get one of those machines to help her up the stairs.
Howard: You mean a forklift?

Sheldon: Sheldon Cooper does not cry.
Howard: That's true, you'd rust.

Amy: Jewelry? Seriously? Sheldon, you are the most shallow, self-centered person I have ever met! Do you really think another transparently manipulative - Oh, it's a tiara! Put it on me, put it on me, put it on me, put it on me.

Penny: You look beautiful.
Amy: Of course I do, I'm a princess and this is my tiara!

Sheldon: Hard as this may be to believe, it's possible that I'm not boyfriend material.
Leonard: Glad I was sitting down for that.