Dr. Isiah Friedlander: Your son, James. He's a good kid?
Michael De Santa: He's a good kid? A good kid? Why? Does he help the fucking poor? No. He sits on his ass all day, smoking dope and jerking off while he plays that fucking game. If that's our standard for goodness... then no wonder this country's screwed.

Cave Johnson: Greetings, friend. I'm Cave Johnson, CEO of Aperture Science. You might know us as a vital participant in the 1968 senate hearings on missing astronauts. And you've most likely used one of the many products we invented - but that other people have somehow managed to steal from us. Black Mesa can eat my bankrupt-...

Caroline: Sir, the testing?

Cave Johnson: Right. Now, you might be asking yourself, "Cave, just how difficult are these tests? What was in that phonebook of a contract I signed? Am I in danger?" Let me answer those questions with a question. Who wants to make sixty dollars? Cash. You can also feel free to relax for up to twenty minutes in the waiting room, which is a damn sight more comfortable than the park benches most of you were sleeping on when we found you. So! Welcome to Aperture. You're here because we want the best, and you're it. Nope. Couldn't keep a straight face.

Dr. Isaac Kleiner: We can't leave without Lamarr. She's around here somewhere...
Alyx Vance: Come on, Dr. Kleiner. We can find you another pet headcrab.
Dr. Isaac Kleiner: No! There's only one Hedy!

Dr. Eli Vance: A-hem! Alyx, why don't you take Gordon along and give him some practice with the Gravity Gun?
Alyx Vance: Sure. C'mon, Gordon. Let's go have some fun.
Dr. Judith Mossman: The Zero Point Energy Field Manipulator is not a toy, Alyx.
Alyx Vance: Ugh, let's get outta here.

Player: No machine should have free will.
Nick Valentine: Why? You jealous you had to turn yours in?

When you are asked, "Where is God? Who is God?" stand up and say, "I am God and here is God, not as yet completed, but still advancing towards completion, just in so much as I am working for the purpose of the universe, working for the good of the whole of society and the whole world, instead of merely looking after my personal ends."

Trevor: I asked for a fair day's pay for a fair day's work. Well, he kinda got a little angry. So, I admit, I kinda got a little angry too.
Michael: Did you kill him?
Trevor: What kinda fucking animal do you take me for? No, I didn't kill him!

Michael sighs with relief

Trevor: But I did kidnap his wife.

Had to be me. Someone else might have gotten it wrong.

I might have had just a bit of Jet before operating. So I nipped a few arteries I shouldn't have? Who hasn't?

Life is a negotiation. We all want. We all give to get what we want.

V: Used to be a media, didn't you?
Regina: Not hard to guess, but I'll give you a point for perceptiveness.

Trevor: Well, hello there beautiful. Here, (hands over money) go buy yourself something nice.
Aunt: This is seven dollars?!?!
Trevor: I said something nice, not something expensive…!

Dom: Did you hear that? What the hell’s that sound?
Marcus: It’s just the wind.
Dom: Yeah, right. When was the last time the wind said 'hostiles' to you?

Judy: Wanna guess what?
V: That if I were an animal, I'd totally be a dog. Because I'm cute, loyal and love to lick eeeeeeverything.

Frank: Jenkins is your lead, right? Is he what everyone says he is?
V: What's everyone say about Jenkins?
Frank: That he's effective. Like any psychopath. Apparently, he's gone a little crazier lately.