Zack: Boy, you get some dirty looks over there when you ask for ice.

Howard: Okay, let me stop you right there. We absolutely know our invention will not be used to destroy the world.
Leonard: How?
Howard: Because no one from the future has come back to kill us.

Sheldon: And last but not least, this is one that I like to call Star Wars Toast because it has a light side and a dark side. All righty, it's time for Dungeons & Dragons.
Bernadette: Dungeons & Dragons? That sounds about right.

Sheldon: Your name is Bernatrix. You are a warrior queen. You're strong, beautiful and tall.
Bernadette: Oh. I like the idea of being tall.
Sheldon: I think you're gonna like a lot of things I have in store. For example, in this world, only the men get pregnant, so your husband is home trying not to pee when he laughs.
Bernadette: This is getting fun. What's next?
Sheldon: You're parched and weary from battle. You stand in front of a tavern that serves the coldest, most delicious ale in all the realm.
Bernadette: Oh, I haven't had a drink in months.
Sheldon: What do you do?
Bernadette: I storm in, slam my sword down, and say, barkeep, bring me the strongest ale you have and serve it in the skull of a goblin.
Sheldon: He wants to see I.D.

Sheldon: You're gonna enjoy this. I designed it especially for you.
Bernadette: Okay, but just for a little bit.
Sheldon: Oh, I have a feeling that once you start, you're not gonna want to or be allowed to stop.

Sheldon: H-O gauge trains are 1/87th scale. N gauge are 1/160th scale. And that brings us to Z gauge, at a - you could easily swallow it, dont ask how I know - 1 to 220.
Bernadette: I'm sorry, I have to ask.
Sheldon: When I was five, I ingested a Z gauge locomotive. I spent the next three days saying, "I think I can pass it, I think I can pass it, I think I can pass it."

Claire: Hey, Raj.
Raj: Hey, Claire. Good, you're here. Guys, this is my friend Claire. We're casually dating, and there's no need for any further questions about it.
Leonard: Would you like a glass of wine?
Raj: I said no questions.

Raj: You can't let this stop you. Almost any scientific advancement can be used for destructive purposes.
Amy: It's true. Even Einstein's theory of relativity was later applied to the development of nuclear weapons.
Penny: E equals MC squared. Yeah. E is for energy, M for mass, and C for the speed of light.
Amy: How do you know that?
Penny: Oh, Leonard mumbles it when he wants sex to last longer.

Leonard: I have to admit, I've been worried about the military applications since we started talking about this.
Howard: Me, too.
Leonard: Why didn't you say something?
Howard: Same reason I don't talk about ass cancer. It's not a pleasant topic.

Bernadette: What is it about trains that you like so much?
Sheldon: What an interesting question. When I was a child, life was confusing and chaotic for me, and trains represented order. I could line them up, categorize them, control them. I guess you could say that they gave me a sense of calm in a world that didn't.
Bernadette: That's lovely, Sheldon.
Sheldon: Well, other than when they're chugging through your bowels, these things are magic.

Zack: So what's your invention?
Howard: Well, we're using quantum vortices to replace gyroscopes in guidance systems.
Leonard: What's neat is that they can maintain angular momentum indefinitely.
Zack: Angular momentum. I was wondering about that.

Amy: I'm getting an earthy note.
Penny: Ah, there's definitely some oak.
Raj: Also, uh, cherries?
Leonard: I smell nothing.
Howard: Really? Nothing?
Leonard: Just a whole lot of Afrin.

Zack: Penny?
Penny: Oh, Zack, hi. You guys remember Zack?
Howard: Yeah, hey, buddy.
Amy: Hello.
Raj: Hey.
Zack: Hey, did you two get married?
Penny: We did.
Leonard: Yeah, mmm-hmm.
Zack: To each other?
Penny: Yes.
Zack: Cool. 'cause other than when you broke up with him and dated me, then broke up with me, and then dated me one more time before going back to him, I was always rooting for you two.

Zack: So how's the science world? What are you guys up to?
Howard: We've actually been working on a prototype for a navigation system we invented.
Leonard: But we won't bore you with the details.
Zack: Are you kidding? I love science. Einstein, Stephen Hawking, Mike deGrasse Tyson.
Amy: Mike deGrasse Tyson?
Howard: Yeah, you know, the boxer who grew a mustache and became a scientist.

Howard: You could put it in a satellite or a rocket, and it'll run forever.
Zack: Cool. Could it be used for missiles and war stuff?
Howard: Yeah, but we didn't create it for weapons.
Leonard: And I doubt the military would be interested in our little guidance system.
Zack: Is it better than the one they use now?
Howard: A lot.
Leonard: Way better.
Zack: Huh. You sure you guys are smart?