Ergo

From the introduction

Ergo is a different direction in the way role-playing games are played. It changes the fundamental make up of a role-playing game by making one simple change. In Ergo there is no gamesmaster, the players get on just fine on their own. They collaborate and co-operate. There is no adversarial gamesmaster whose evil plans need to be thwarted and adventures need to be beaten. Ergo does not have its own rule set. The concepts and mechanisms can be used with any set of role-playing rules. Some rule systems will be easier to use without a gamesmaster than others. Ergo was written with a modified version of the FUDGE role-playing rules in mind.