Raj: You guys kiss and hold hands.
Leonard: I've seen him do it. It's not romantic.

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.

Howard: You know, when I was a kid I loved going there but I could never get a ride.
Raj: Ooh, what if we got a van and drove around, and picked kids up?
Sheldon: Nice! Like at parks and schools.
Howard: Toy stores, puppet shows.
Leonard: Hold on, so your idea is to get a van and cruise the streets looking for kids to pick up?
Sheldon: Yes!
Leonard: And are you going to use candy to lure them in?
Raj: We are now!

Sheldon: I have some odd freckles on my buttocks. Can I make an appointment for you to look at them?
Emily: Erm, okay, I guess.
Amy: I'm with him three years, nothing. She's with him two minutes and he's taking his pants off.

Amy: Can you see how a grown man and accomplished scientist who invests in a store that sells picture books about flying men in colorful underwear might be wasting both his financial and intellectual resources?
Sheldon: No.
Amy: Then I think it's a terrific idea.
Sheldon: Great! Wait until you hear about our van.