My game group played Fudged Mouse Guard a few weeks ago. It takes the excellent Mouse Guard RPG–a game of intelligent mice with medieval-level technology–and converts the system to Fudge (every stat is a score from -4 to +4, and you roll dice that modify your score up or down for a final result, which is compared to a target difficulty).
The original Mouse Guard system is a simplified and heavily modified version of the odd Burning Wheel system. The conversion to Fudge can’t be exact.
It isn’t, but Fudged Mouse Guard fits the world well, and converts all the important statistics. We were able to play in the Mouse Guard world effectively, using skills and abilities, and combat involved simply trading blows. It works.
I did encounter one problem: The Fudged Mouse Guard document lists no example enemies, and provides no guidelines for enemies’ power level. I guessed at the stats for enemies, which turned out to be low. The PCs defeated all their enemies within three rounds. The original RPG’s unique combat system doesn’t translate directly to a traditional RPG’s mechanic of trading blows, so more direction there would be helpful.
Overall, though, the game went smoothly and we had fun. You can view our character sheets to see the stats used in the system.