Open Quartz is a project to supply GPL'ed artwork in the form of PAK and WAD files to create a fully GPL game based around the GPL'ed quake sourcecode.
This includes models, maps, soundfx and textures.
Interesting Quake conversion.
This set off my virus scanner. Avast reports it as "fileRepMetagen(drp)" Maybe I'll try the Linux version a bit later if I get time.