The Dark Mod was originally built as a modification to Doom 3 (idTech 4) but has recently been released as a freely available stand-alone game. This is a good example of what can happen when individuals, groups and teams have access to the right type of resources with little expense but their time, energy and ideas. Well done Broken Glass Studios. Download and information available from their website -
http://www.thedarkmod.com/
