Sheldon: There's something I need to tell you.
Leonard: Okay.
Sheldon: I can't tell you.
Leonard: Why?
Sheldon: I can't tell you why I can't tell you. So I guess there's two things I can't tell you.
Leonard: I wish there were more.

Leonard: Okay, I think I understand.
Sheldon: You do?
Leonard: The guy who seems like an emotionless robot is you, but your relationship with Amy is causing you to transform into a red-blooded man with sexual desires.
Sheldon: That is literally the stupidest thing I've ever heard.

Howard: The other astronauts are being mean to me.
Bernadette: What are they doing?
Howard: Well, like for instance, the other day when I was asleep, one of the guys went on a space walk and glued a big-eyed rubber alien mask to the outside of my window. When I woke up, I screamed for like nine minutes.
Bernadette: Oh, Howie.
Howard: You can see it if you want. It's on YouTube. Google astronaut screams for nine minutes.

Sheldon: Leonard, maybe you'd like to go with them to meet girls.
Leonard: Why would I be interested? I have Penny.
Sheldon: Yeah, for now. But that woman has a death wish, Leonard. She talks to strangers, she pets unfamiliar dogs, and it is ridiculously easy to break into her apartment. If I were you, I'd get a back-up.

Amy: You slept with him?
Penny: I didn't know what else to do. He had those big, sad eyes.
Bernadette: Oh, sure, you had no choice.

Sheldon: Okay, my turn. Let me talk to him.
Leonard: Go ahead.
Sheldon: 2311 North Los Robles Avenue, Pasadena, California to International Space Station. Can you read me? Over. (Makes static noise)
Howard: Yes, I read you, Sheldon.
Sheldon: Copy that. Over. (Static)
Leonard: What are you doing?
Sheldon: I am talking to a man in space. If you don't have the (static) then he might as well be at the Coffee Bean over on Lake Street.
Howard: You're out of your mind, Sheldon!
Sheldon: That's a negative. My mother had me tested. Over.

Raj: What's the big deal? You guys are bringing your girlfriends. I didn't want to sit by myself.
Sheldon: The big deal is I was expecting us to be an intimate group of five. Now, we're going to be a faceless mass of six.

Leonard: It'll be fine. Just, uh, pretend he's Wolowitz.
Sheldon: Hmm. Do you like Raisinets?
Stuart: I can take them or leave them.
Sheldon: At the movies, Wolowitz always eats Raisinets.
Stuart: Would you feel more comfortable if I ate Raisinets?
Sheldon: Well, it's hardly my business what you eat. As long as it doesn't crunch during the film and it's Raisinets.

Amy: Penny said she's not sure she wants to be Leonard's girlfriend anymore.
Sheldon: Wrong. She just took a sip from his Diet Dr. Pepper.
Amy: So?
Sheldon: So, if she wants to end her pair-bond with Leonard, why on earth would she guzzle a witches' brew of his soda and spit?

Stuart: Raisinet?
Sheldon: Shh, we're trying to watch the movie. (To Amy) This is not working out with him.

Sheldon: *Knock, knock, knock* Leonard? *Knock, knock, knock* Leonard? *Knock, knock, knock* Leonard?
Leonard: What?
Sheldon: Are you sleeping?
Leonard: I was. Now I'm having a nightmare.

Sheldon: Oh, I was having a little trouble sleeping and I just thought, uh, seeing as you're up, we could talk.
Penny: Talk about what?
Sheldon: Oh, I don't know. Uh, weather. Uh, fish you could do carpentry with. Why Leonard is such an attractive and desirable boyfriend. Yeah, pick one. Your choice.
Penny: Sheldon.
Sheldon: Did you know that Leonard has a perfect driving record and enjoys the insurance discounts that go along with that? Hubba-hubba.
Penny: Okay, go home, crazy man.
Sheldon: Yeah. Did you know that while Leonard is not considered a tall fellow in our country, in today's North Korea, he's downright average. Hey, talk about a keeper.

Sheldon: My point is, I don't like when things change. So, regardless of your feelings, I would like you to continue dating Leonard. And also, while we're on the subject, you recently changed your shampoo. I'm not comfortable with the new scent. Please stop this madness and go back to green apple.

Amy: (Puts Penny on hold, answers a new call) Hello?
Sheldon: Yeah, just a heads-up: Penny knows that you blabbed about Leonard. She's pretty mad.
Amy: I know. She's yelling at me right now.
Sheldon: All right then, so we're all on the same page.

Bernadette: Why don't you stand up to them?
Howard: What am I supposed to say?
Bernadette: I don't know. Say, being mean is lame, what's cool is being nice.