(Sheldon knocks on Penny's door three times)
Penny: Who do we love?
Sheldon: Penny. (Knocks 3 times)
Penny: Who do we love?
Sheldon: Penny. (Knocks 3 times)
Penny: Who do we love?
Sheldon: Penny.

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: I'm too small for Twister. And roller coasters. And sitting with my feet on the floor. Hope you enjoyed the prenatal cigarettes, Mom.

Bernadette: Doesn't he know you have a boyfriend?
Penny: She doesn't have a boyfriend, she has a Sheldon.

Howard: I thought you didn't like Facebook any more.
Sheldon: Don't be silly, I'm a fan of anything that tries to replace actual human contact.