There are pirates though these seem to mainly be NPC though I have spotted a few PC pirates (and delt with them accordingly!)
There are dozens of different maps and games running with unlimited ot limited corporation memebrship sizes enforced.
Player can also sub-contract to corporations to operate the colony supply runs. I've seen a few offer up the services of thier barges for hire.
The wars or skirmishs between the larger of the numerous corporations are interesting as others seek to affiliate to one side or another. Myself, I just move in after the battle and loot the debris Ferrengi style!!
I received the UFO - Alien Unknown sequel trilogy for Christmas, so I'll probally be tied up in that for the next few years, bearing in mind that it takes a couple of years to complete just one game of UFO - Alien Unknown from start to finish.
The 1990's PC classic is now downloadable as freeware now under UFO Gold or UFO - Allien Unknown Gold Edition, which has been fixed to run on Vista and XP.
As an online game with players involved in a joint X-COM project to defeat the server contrlled "Aliens", this would be the ultimate online game experience, especially if the "Away Missions" , "Base Assaults", "Base Defends" and "Terror Missions" could be rigged as first person team shoot em ups!!