Fate Roleplaying Game.
Fate is really cool because it is a specific take on the Fudge RPG engine but moves beyond it to make something unique. It blends storytelling with a flexible engine that scales up and down with little fuss. Plus the support for it is great with new supplements coming it regularly.
And it's CC-BY which means you can use it for your own projects.
@craigmaloney In many ways, Fate is what Fudge should have become. But instead, Fudge refused to evolve and Fate started it's own community. Oddly, I don't think it stole members from the Fudge community so much as finding an audience Fudge couldn't attract. I wish we could have kept them together, but now Fate only acknowledges its Fudge roots because of the legal requirement.