Freeform Interactive sends along word that their online FPS/RPG hybrid Purge, originally released in 2002, is now available as a free download (350MB).
Purge is a persistant, multiplayer online, FPS/RPG hybrid powered by a highly modified Lithtech Talon technology. Originally released as a retail game in 2002, Purge is an online-only PC computer game. It is a hybrid First-Person-Shooter / Role-Playing-Game set in the near future accounting a war between the diametrically opposed forces of science-fiction (the Order) and fantasy (the Chosen). Technology versus magic. Science versus religion. It is a great divine war, where followers pray for intervention from the extraterrestrial deity Evod or the supernatural deity Mabus.

Although, Purge still requires a registration key to unlock all the class, this is completely and 100% free. There are no strings attached. The key system is still necessary as a unique user identifier for Purge to save your Role-Playing Game character stats on the game servers. When you have installed Purge, simply request a key. In fact, the keys are now handled entirely by the Purge community now and not by Freeform Interactive.