Howard: Here's an approximation of the spare parts available on the Space Station. We gotta find a way, using nothing but this, to reinforce this so the waste material avoids the spinning turbine.
Raj: You mean so it doesn't hit the fan?

Howard: Ok, now, this is an exact duplicate of The Wolowitz Solid Waste Disposal System, as deployed on the International Space Station.
Raj: Don't you mean the Wolowitz Solid Waste Distribution System?

Sheldon: Answer the phone, Leonard.
Leonard: No! There, it went to voice mail.
Sheldon: Aren't you going to check your messages?
Leonard: No.
Sheldon: You have to check your messages, the leaving of a message is one half of a social contract which is completed by the checking of the message. If that contract breaks down then all social contracts break down and we descend into anarchy.

Leonard: Well, what are you gonna do?
Howard: I'm gonna figure out how to fix it, then I'll tell them.
Leonard: So, what do you need us for?
Raj: He can't figure out how to fix it.
Howard: Hey, you said you were gonna be supportive.
Raj: I'm trying, but you have to admit this is pretty damn funny.
Sheldon: I agree. It's the juxtaposition of the high-tech nature of space exploration against the banality of a malfunctioning toilet that provides the comic fodder here. Check your messages.

Leonard: Thanks for closed captioning my pain, Raj.

Howard: Okay make your little jokes, but out of the four of us, I'm the only one who's making real world contribution to science and technology.
Rajesh: He's right, this is an important achievement for two reasons. Number one and of course number two!

Penny: Morning. What’s up?
Leonard: Nothing. We just pulled an all-nighter trying to fix a zero-gravity ... pasta maker.

Sheldon: Why does Leonard get to go?
Wolowitz: Because he's upset over his situation with Penny, and if I have to hear about it again, I'm gonna kick him in his ovaries!
Leonard: Thanks for understanding.
Howard: I've got your back, sister!

Stuart: Here, Sheldon, I pulled the new Hellboy for you. It's mind-blowing.
Sheldon: Excuse me. Spoiler alert.
Stuart: I didn't spoil anything.
Sheldon: You told me it's mind-blowing.So, my mind is going into it pre-blown. And once a mind is pre-blown, it cannot be re-blown.
Stuart: I'm sorry.
Sheldon: Said the Grinch to Christmas.

Howard: Guys, we have a code red.
Sheldon: Do you mean code red for the hospital emergency alert, code red the computer worm, or Code Red the cherry-flavored soft drink from the makers of Mountain Dew?

Raj: Okay, look. Instead of trying to reinforce this structure here, what if we just ran another line, bypass it entirely?
Sheldon: It won't work. The diameter of the tubing is insufficient.
Raj: What if we reposition the collection tank?
Sheldon: It won't work. No way to mount it.
Howard: Okay, here's an idea. What if I change my name and go live with my cousin and her husband Avi in Israel?
Sheldon: That could work.

Leonard: Hey, Stuart, I need to talk to you.
Stuart: Sure, what's up?
Leonard: I think I gave you bad advice about Penny, and I want to apologize.
Stuart: No, your advice was great.
Leonard: It was?
Stuart: Yeah, going slow really worked.
Leonard: You're kidding. Never worked for me.

Sheldon: For what it's worth, my mother says that when we deceive for personal gain, we make Jesus cry.

Sheldon: I must say, Howard, I think a detailed letter to MIT describing your current circumstances might entitle you to a refund on your master's degree.

Leonard: Just think. Thanks to your hard work, an international crew of astronauts will boldly go where no man has gone before.