The first scene in the lab, in which the nerve gas begins eating through their protective suits, and upon learning they have to inject the antidote straight into the heart with a very long needle. Not the danger itself, of course, but the reaction to it:
"Look how big this is; you want me to stick this into my heart? Are you fucking nuts?!"
The streetcar driver after the chase scene.
"Shit! This sucks! Where that son of a bitch at? That motherfucker ain't safe nowhere!"
Mason on the car phone.
"I'm only borrowing your humvee."
Goodspeed: May I also suggest, uh, a haircut? Mason: Am I out of style? Goodspeed: Unless you're a 20-year-old guitarist from Seattle. It's a grunge thing.
Then later, there's the one between Mason and the hairdresser:
Hairdresser: Ugh! Who did this to you? This isn't right! In fact, it's nasty! Mason: It's a..."grunge" thing. Hairdresser: Well, it's some kind of thing...
And of course the follow-up after Mason handily PWNs the agents guarding him:
"Okay, I don't want to know nothing. I never saw you throw that gentleman off the balcony. All I care about is: are you happy with your haircut?"
The exchange in the morgue:
(Mason and Goodspeed have just killed a squad of Hummel's marines. A corpse's foot starts twitching.) Goodspeed: Okay, look...you've been around a lot of corpses. Is that normal? Mason: What, the feet thing? Goodspeed: Yes, the feet thing! Mason: Yeah, it happens... Goodspeed: Look, I'm having trouble concentrating...can you do something about it? Mason: Well, like what? Kill him again?
The whole morgue scene is funny and good for character establishment. It's the first and only time we see Mason looking nervous and Goodspeed being the badass, since Goodspeed's really in his element with the VX.
"I just bring it up because... it's you. You're the Rocketman."
Kid on motorcycle: Hey man, you just fucked up your Ferrari. Goodspeed: It's not mine. [kid laughs]And neither is this.
Mason: You sure you're up to this? Goodspeed: I'm doing my best. Mason: Your best? Losers always whine about their best. Winners go home and fuck the prom queen. Goodspeed: Carla was the prom queen. Mason: Really? (Goodspeed cocks his gun) Goodspeed: Yeah.
The first mention of Mason.
Womack: And if he hits the streets... Chief Justice: He's not gonna "hit the streets", Jim! Thirty years ago, he was a highly trained SAS operative. He's my age now, for Christ's sake. I gotta get up 3 times a night to take a piss!
The definition of a combat situation.
An incursion underwater to re-take an impregnable fortress held by an elite team of US Marines in possession of 81 hostages and 15 guided rockets armed with VX poison gas.
Mason: Last time I swam that channel I was your age, so I'm fucked either way.
A rather dark one when the president is being told how much damage a single missile filled with the gas could do.
President: What's the estimated body count for each missile? Adviser: Sixty or seventy. Chief of Staff:[relieved] Oh, that's not so bad. Adviser: Thousand. Seventy thousand. Dead. One teaspoon of this hits the floor, it's lethal up to... a hundred feet. One teaspoon of this shit detonated in the atmosphere... will kill every living organism in an eight-block radius. Get the point?