Penny: Oh, I love the observatory. They tell you your weight on all the different planets. Yeah, it's always bikini season on Venus.

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.

Sheldon: I mean, it's not that I think we're living in sin, but I do like the idea that our next act of intimacy will be a legal requirement.

Amy: Maybe we should just get married at City Hall and forget about everything else.
Sheldon: City Hall, hmm. I do like metal detectors and the sound of permits being denied.

Sheldon: Neither of them will be the actual cake. I'm just using it as a bargaining chip to get Amy to agree to the whole wedding party getting rings and us getting one ring to rule them all.
Howard: I forget, which mental hospital are you guys registered at?