http://www.insurgencymod.net/ is a HL2 mod, and for the ones who don't know what that is, it's the Half-Life 2 Engine, and therefor everyone who have either purchased/installed Half-Life 2, Counter-Strike: Source or any other HL2 game in particular is able to play this game. I most say, it's the most realistic game I've seen so far, even for a mod to be. It covers just about everything real life, in Iraq, where it takes place with the U.S Marines against the Iraq Insurgents. You have to Sprint, Crouch, Duck, and alot other stuff just to survive, and since you all seem to be very cooperative, this game is perfect as it's all about teamplay. The Insurgency Mod is available free to download on their homepage, provided above, or free via the Steamstore -> Mods -> Insurgency -> Install .. Although, i'd prefer the 2nd. option, as Steam will automatically update and install latest patches for Insurgency.
Go give it a try, god damnit :d
My steamacc (if you wanna add me): Alfanir
I call myself zimPe ingame. 
And yes, it's ONLINE .. About 60 servers online with over 10 players each server this moment, and it's increasing._________________
:: ~Alts~
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