Awesome, a place to trade war stories. Let me think...
another thread.)[/I] Playing through No Mercy, we're on the finale map. I've got my auto-shotgun and I'm just wailing on everybody. The helicopter swoops in, just as we take down a tank, and I yell for everyone to book it. I'm the last one off the roof, and the others are running and gunning. One person gets jumped by a Hunter; I unload the rest of my ammo into the Hunter to shreds and hold off the horde with my pistols to let the other player up. We continue running. By now, one person is already on the heli, and the other is mid-jump.
All of a sudden, just as we're about to jump onto the heli ourselves (literally right next to it), the player who got jumped is swarmed and knocked down. Seeing this, I turn and run all the way back to the ammo pile, reload my shotty, come back and unload into the horde that has formed. I manage to save the person, get them back to their feet while the two in the heli cover us, and then hold off the horde as the player gets on the heli. All before jumping on myself and flying away.
Left 4 Dead - Playing through Blood Harvest, on the finale map again. Myself, two friends and a bot. We've managed to hold off the horde in the house successfully with little damage taken (due to liberal use of pipebombs), so, when the APC arrives, we feel confident in our ability to make it. We all go scampering downstairs and around the corner, unloading into the horde as we run.
All of a sudden, a tank comes charging out of nowhere and smacks one of my friends. By this time, I've already made it to the APC, but when she yells out for help, I turn around to see what's going on. She's still back by the porch, with the horde between her and the APC, and a tank wailing on her. I swear under my breath and go booking it back across the field. I manage to actually get there to help, and unload my shotty into the tank, killing it. Just as I'm about to pull her back up, though, another tank shows up and smacks me away. Luckily, it was in the direction of the APC, but before I can collect my thoughts, the second tank has already finished off my friend. So I just turned around and ran onto the APC.
Not quite as successful, but still pretty epic.
Call of Duty - I'm talking about the original here, just so everyone's on the same page.
The beginning of the second level of the game, where you're just entering Ste. Mere Eglise, and you're running across the field littered with craters and dead cows. There's a wooden fence on the opposite side of the field, and buildings beyond it. One of your squadmates gets shot down, and another NPC grabs him and starts dragging him to cover. All while an MG42 starts unloading on them.
I replayed that over and over until I made sure that they both got to safety.
Call of Duty: United Offensive - The Noville mission, where you are advancing down the main street towards the mansion in the middle of town. There is a point when a German slams open a window and pops off a Panzerschreck shot at one of your tanks, blowing it up. I reloaded and replayed that part so many times, just trying to take that guy down before he blew up the tank. I even managed to hit him before he could, a few times, but it was scripted that it would happen, so the shot would always go off. I was disappointed, to say the least.
Half-Life 2: Episode 2 - The ending. 'nuff said.
System Shock 2 - The big reveal regarding SHODAN and Polito about half-way through.
BioShock - "Would you kindly?" 'nuff said.
BioShock - My proof that hacking the health stations is more than worth the time and effort: In the hallway leading towards Dr. Steiner, I hacked the health station and healed myself. I walk through the door, watch the mini-cutscene-thing, then proceed to fight him. I rush into the room, we trade shots, then I lose track of him. I'm under the stairs when I hear a scream. Rushing back up the stairs, I go out into the hall, only to find Dr. Steiner dead right beside the health station I had hacked. That's right, I killed the first boss by hacking a health station. I was rather impressed with myself, I must say.
Shadow of the Colossus - The entire game.
That's about all the big ones I can think of.