Penny: Amy, little vixen. Just working it under all those layers of wool and polyester.

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.

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

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.

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.

(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.