Evil, faceless corperations or governments being the main villains or/while a bunch of hip, young and charismatic freedom fighters take the part of the protaganists (Half Life 2, Resident Evil, Alien, Army of Two, Red Faction, Unreal, Armoured Core, Mirror's Edge, Final Fantasy 7...the list goes on).
While I'm fully (and shamefully) aware that the 'stick it to The Man' theme is popular to the youth of today (I should know, I'm one of them) but it has been done to death now. Some people get tired of hearing about space marines and I get tired of hearing about X Corp plot to make the masses suffer and obey so they can line their pockets with gold/gain power.