Penny: It has also been shown to cause significantly fewer side effects than other oral contraceptives. Although it can cause acne, which if you ask me kind of increases its effectiveness as a contraceptive.

Sheldon: Woman, you are playing with forces beyond your ken.
Penny: Yeah, well your Ken can kiss my Barbie.

Raj: [to Amy] If you were having Sheldon's baby, would you really want him in the room?
Penny: Yeah, if he's in the room when they're making the baby, I'll give you $10.

Penny: I mean, who even reads Scientific American?
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

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.