Leonard: Once you open the box it loses its value.
Penny: Yeah, yeah. My mom gave me the same lecture about my virginity. I gotta tell you, it was a lot more fun taking it out and playing with it.

Leonard: You went to the comic book store by yourself?
Penny: Yeah, it was fun. I walked in and two different guys got asthma attacks. It felt pretty good.

Penny: Sorry, Stallion. Your weird friend Giraffe is here.

Amy: That would be my boyfriend. Happier playing his dopey Star Trek game with his friends than hanging out with me
Penny: Wars.
Amy: What?
Penny: Star Wars. They get all cranky when you mix the two up.
Amy: What's the difference?
Penny: There is absolutely no difference!

Leonard: Okay, uh, how do I put this? Um, are you familiar with Darwin's observation of the finches in the Galapagos Islands?
Penny: Did they make a movie about it?
Leonard: No.
Penny: Then no.

Amy: I'm dating Sheldon Cooper
Penny: Yes. On purpose.
Amy: He's handsome, he's lanky, he's brilliant, and his skin has that pale, waxy quality.
Penny: Well, sickly is the new sexy.

Penny: You know I'm a big believer in breaking bad news to a guy when you're in bed with him. That's how I told my high school boyfriend I slept with his brother. That's how I told his brother the same thing.

Bernadette: Oh, I don't know. I don't want to manipulate him with sex.
Penny: Oh, sweetie, that's what sex is for.

Penny: Hey, what are you guys doing here?
Howard: We're grown men, we drink at bars.
Penny: No and no. Everything okay with you and Bernadette?
Howard: Oh yeah, sure.
Penny: You and Amy? Good?
Sheldon: Oh, better than good.
Penny: You know those girls text me every detail of their lives as it happens.

Penny: Sheldon, that's not what girlfriends are for. Although you don't use them for what they're for, so what do I know?

Penny: You mean like a beta test?
Leonard: Well, technically, this would be an alpha test. A beta test requires people that weren't involved in the development of the appli-
Penny: Seriously, do I not get credit for knowing beta test?
Leonard: No, absolutely you should.

Penny: Bug report: when a guy asks me to spend some time with him, maybe he plans something a little more interesting than hanging out at home and watching TV.
Leonard: Even Doctor Who?
Penny: Even Doctor Who.

Penny: You mean, like a date?
Leonard: Not like a date, a date.

Penny: Did Sheldon change the Wi-Fi password again?
Leonard: Yeah, it's "Penny already eats our food she can pay for Wi-Fi". No spaces.

Penny: Leonard, you're looking for a way to sleep with both women and have everybody be happy about it.
Leonard: Now we're getting somewhere.
Penny: What does your gut tell you?
Leonard: Go ask Penny; she'll know what to do.