Leonard: Holy crap, are you connected to the Oak Ridge National Laboratory?
Sheldon: Yes. I'm using their Cray Supercomputer to analyze shuffling patterns.
Leonard: Sheldon, that computer is used for national defense. Hacking into it is a federal crime.
Sheldon: Relax, we're not under attack right now.
Leonard: Okay, I'm leaving before the black helicopters get here.

Priya: Why didn't you wear your contacts? Don't you like them?
Leonard: No, no, I do. Its just I knew I was having curry tonight and I only want one part of my body to burn at a time.

Leonard: I just know the longer we wait to talk about it, the weirder it gets.
Penny: Sweetie, can I just be the girl tonight?
Leonard: Absolutely. You're the girl, I'm the guy. Now, you watch your football game while I make you a little plate here.

Leonard: I couldn't say that. I would have to say, "You were terrific and I can't wait to hear you sing again."
Sheldon: Why?
Leonard: It's the social protocol. It's what you do when you have a friend who's proud of something they really suck at.
Sheldon: I was not aware of that.
Leonard: Well now you are.

Sheldon: I'm sorry, Leonard. This is Toby Loobenfeld. He's a research assistant in the particle physics lab, but he also minored in theater at MIT.
Toby: It was more of a double major actually. Theater and physics. You can guess which one my bourgeois parents pushed me towards.
Leonard: Yeah, I got it.

Howard: Nice to see that the gals are getting along.
Leonard: Gals? Who are you, Fred Flintstone?

Leonard: Hey, how about if we pretend we're actually on a first date? See how that goes.
Penny: Okay.
Leonard: So, Polly, tell me about yourself.
Penny: It's Penny.
Leonard: Oh, sorry, yeah. Awkward.

Leonard: Uh, let's see. Uh, I am an experimental physicist at Cal-Tech, most of my research is with high-powered lasers, and, oh, I've just gotten a big government grant to see if they can be used to knock out incoming ballistic missiles.
Penny: Wow. Can they?
Leonard: Oh, God, no. The money's pretty good. And I used the equipment to make my own Bat-signal.

Penny: You are so funny.
Leonard: Good. Remember that when I take my shirt off.

Penny: You're over-thinking this.
Leonard: No, I'm not.
Penny: Yes, you are. You always over-think things.
Leonard: Ah, now there you go. Always made it worse.

Penny: See, this is where everything goes wrong, when we talk.
Leonard: Well, I don't know how you have a relationship without talking.
Penny: Hey, I went out with this guy TJ for eight months. We never talked. To this day, I don't even know what TJ stands for.
Leonard: Wait, if you guys didn't talk, what did you ... Never mind, stupid question.

Penny: Well, that was fun.
Leonard: Yeah, except for when I got the foot cramp.
Penny: You hung in there, though.
Leonard: Well, there was a lot at stake.

Penny: Hey, I just remembered. I still got one of your inhalers.
Leonard: I can't believe you kept this.
Penny: Yeah, I was gonna throw it away, but I just couldn't.
Leonard: That is so sweet. In 25 to 30 minutes I'm gonna show you how much this means to me.

Penny: No, that's okay, Bernadette. Sometimes these things just don't work out.
Leonard: Yeah, it's all good. We'll always have feelings for each other.
Bernadette: Oh, that's nice.
Leonard: See, she knew what always meant.

Leonard: What do you want?
Sheldon: It's not what I want, it's what evolution wants. Human beings are primates. Primates have evolved to live in groups, both for protection and support.
Leonard: But you don't like other people.
Sheldon: I do tonight. It's scary over there.
Leonard: It's getting scary here, too.