Favorite helicopter boss/encounter in a video game

There's alot of helicopter battles in video games especially now days in third/first person shooters.
List your favorite here! plz...
 
Mine is probably the one in the first stage of Super C or the one in MGS.

Well my least favorite is the one in Half-life 2. 
 So annoying.

Don't know if it counts, but that flying thing you find in Killzone 2 for the first time. They way it moves is just awesome.
 
Besides that, I'd have to go with the Liquid Snake helicopter fight in MGS.

MGS or Uncharted 2 helicopter encounters...

Off the top of my head, I have no idea. I can't remember all that many helicopter boss fights. It was an awesome part when that dude (I think his name was Mike) was giving you support from above with a helicopter in RE4, but that wasn't a boss fight since he was on your side. Yeah, I can't really think of anything.

The MGS boss is epic and involving but most helicopter battles now days just amount to: Shoot cockpit or pick up a rocket launcher and shoot down the helicopter.

The helicopter encounter while on the train in Uncharted 2 FUCKING PISSED ME THE FUCK OFF!!!ONE!!!111!!!!!!!

My favorite is the the CoD4 sniper mission where you just splatter that helicopter pilot's brains all over his cockpit. 
 
Runner up goes to Prototype for the number of helicopters I have cannonballed out of the sky. (But seriously, an X and B button combo for that move is mad stupid.)

Theres at least one helicopter fight/encounter in every new(maybe more frequent in b and c grade games) third/first person shooter.
Dark sector had two(I think), TImeshift, Ninja Blade, Blacksite, HL2 and Bionic Commando had one just of the top of my head.

I had a pretty sweet moment in MGS3's mountain range areas, I got spotted and the only place to hide was a little slit of a crawlspace in the mountainside, but they call in helicopter support in that area I guess. 
 
So the heli leveled itself out just outside the cliff edge so it could peer into my spot and I assumed I was boned, but I figured I'd let loose with my sniper rifle, and it actually killed the pilot.

I can only really think of the one in Half Life 2... and the one in Timesplitters (FP maybe?), i think, when your on the train? Was that a halicopter? It was awesome anyways.

Doesn't Halo 1-3 or Army of two 1-2 contain any helicopter bosses? I've never played any of thoose games.