FPS = Planetside2 - 3 factions all fighting for territory like risk on 3 different continents (tons of different guns, planes, and tanks)
A lot of ex military play so its fun being in a 40 man platoon taking territories.
Plus its free to play but you can get sony money and buy guns quickly if you don't want to earn them. I spent at least $300 bucks on station cash, because I have a job and want the best shit heh.
Best of all time would have to be - Counterstrike - best map Dust2 (Game was so addicting I had to drop classes one semester back in college to not fail lol)