Penny: You guys should've seen Leonard when I first met him. There was no eye contact. He was either looking up at the ceiling, or down at his shoes.
Amy: I'm drunk.
Penny: You know, for the first couple of months, whenever I would take off my bra, he would giggle and say, oh boy, my breast friends.

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

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

Leonard: What am I supposed to do?
Penny: Err, keep your mouth off other women.

Penny: Give my friend his stuff back.
Tod Zarnecki: I don't know what you're talking about.
Penny: Well then good news. Today's the day a girl's finally going to touch you in your little special place. *Kicks him in the groin*

Raj: Come on, dude, bros before ... my sister.

Sheldon: I've never said these words before, but good job, Howard.