Penny: You know, I remember my first bikini wax. My sister did it with duct tape and melted Crayolas. To this day, I can't look at a box of crayons without crossing my legs.

Penny: At one point, they had me figure out how to get a banana out of a puzzle box.
Leonard: Wait, Sheldon gave me a banana in a box. He was testing me, too.
Penny: Unbelievable.
Leonard: And how could a chimp even solve that? That was impossible.
Penny: Really? You couldn't get it out?

Leonard: If I take it off, Sheldon wins.
Penny: Sweetie, every night you don't kill him in his sleep, he wins.

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

Bernadette: Gosh, Amy. I'm sensing a little hostility. Is it maybe because like Sheldon's work, your sex life is also theoretical?

Howard: Are you listening to yourself?
Sheldon: I always listen to myself. It's one of the great joys of my life.

Sheldon: You know what they say. Revenge is a dish best served nude.