Original Dungeon Keeper for free on GoG and several others 90% off there. Includes Dungeon Keeper 2, the new Rise of the Triad, System Shock 2, Trine and several others
Turns out it's a group of three friends abusing the votekick system.
http://steamcommunity.com/id/AdventuresWithBill
http://steamcommunity.com/profiles/76561198009592509
http://steamcommunity.com/profiles/76561198030802187
They have been banned permanently.