Open Source Rules -- Chupa Open Roleplay System
This universal system was originally created by Lonnie Ezelle and Chuck Tinsley of the Dragon's Landing Podcast and released with a Creative Commons License. We never quite got around to releasing the 2nd edition which opened the doors highly diverse roleplay experiences like roleplaying as cities. 2nd edition will be released with optional modules for different campaigns including Madness of Cthulhu and The Jane Austin Roleplaying Game.