I’m not role playing at the moment, but if I was I think FATE could well be the system that I would be playing. It is a sweet little system that really challenges the whole group to build a narrative together, still with a GM but giving they players a bigger voice in the plot.
One of the mechanisms for this is trading good results for bad to gain fate points that can be used later to modify future bad results. It sounds weird but there are better explanations than mine. One can be found in a short video at this really cool Kickstarter for FATE tokens by Campaign Coins
While you’re there I recommend subscribing – this project is going to go off, and the tokens are really nice (I’ve already jumped in).