Raj: My father thinks the reason I can't make a relationship work is because I'm spoiled.
(Everybody is quiet, looking sheepishly away from Raj)
Leonard: I'm sorry, is he waiting for someone to disagree?

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: 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.

Amy: What is this?
Sheldon: I'm mapping basic topics of conversation and with whom they can be discussed.
I call these circles "Zones of Privacy". Don't Google that unless you want to see pictures of people's genitals.

Bert: I met her on G-Harmony. That's a Web site for geologists to find love.
Amy: That's a real thing?
Bert: Yeah. Their slogan is "We're all about dating and not the carbon-14 kind".

Sheldon: Two years ago I got my driver's license.
Amy: What? Why didn't you say anything?!
Sheldon: I like being chauffeured around. It makes me feel important.
Amy: So when I got up at 4:00 AM to drive you across the desert to an antique train museum, I didn't have to?
Sheldon: No, you didn't. But keep in mind, I felt extremely important.