Leonard: Wow. How do you get an entire lecture hall to flip you off at the same time?
Howard: Apparently, if you're Sheldon, all you need to do is turn your back.

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.

Raj: Dance number aside, I'm so not gay.

Penny: Mrs. Cooper? Hey, it's Penny. I think I broke your son. Hold on. Talk to your mother.
Sheldon: (Crying) Mommy, I love you. Don't let Spock take me to the future!

Raj: I know the feeling. It's like accidentally walking into a gay bar and then having no one hit on you. It happened to a friend of mine.