44 Productions
   Online store offers Signature, an universal RPG as a PDF download.
   http://mysite.verizon.net/resq2tgs/

Mythic Role-Playing
   Assists game masters in creating adventures without preparation. For use as a stand-alone role-playing game or as a supplement for other systems.
   http://www.mythic.wordpr.com

Necrotech's Universe of T.W.E.R.P.S.
   A space opera setting for The World's Easiest Role-Playing System, presented in English and German.
   http://www.twerps.de/

Shards of the Stone
   Detailed world setting with multiple realms divided by schisms of time. Rules available for FiveStat, Fuzion, and d20 conversions.
   http://www.shardsofthestone.com/

Wushu
   Universal role-playing game with martial arts and pulp era expansions.
   http://bayn.org/wushu/