Penny: Well, I'm sure the new people will be just as quiet.
Sheldon: You can't know that. How can you possibly know that? Penny: You know what? Anyone could rent that apartment now. An opera singer, the cast of Stomp, a tap dancing pirate with a wooden leg.
Leonard: Why are you making it worse?
Penny: I tried making it better, he wouldn't go for it.

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.

Wolowitz: Penny, let me take this opportunity to point out that you are looking particularly ravishing today.
Penny: Not with a thousand condoms, Howard.
Wolowitz: So there is a number.

Penny: Leonard, and Howard, and Raj, they aren't like other guys. They're special.
Alicia: Okay, they're special, and?
Penny: Well let's see how can I explain this. Um. They don't know how to use their shields.
Alicia: Shields?
Penny: Yeah. You know like in Star Trek and you're in battle, and you raise the shields.
*Realizing what she said* Where the hell did that come from?

Howard: Enough with the guilt, ma. We'll still see each other. I'll come over every night and have dinner with you.
Mrs. Wolowitz The hell you will! What am I running here, a fancy restaurant? Does this look like the Olive Garden?