"The Dresden Files Roleplaying Game" uses the Fate system; a very narrative system in which each character doesn't just have skills and attributes but aspects; freeform traits that are true and can be made relevant to the narrative for a bonus - or for a penalty and a Plot Point to use later. Fate was chosen over the more popular open gaming d20 system because it makes it easier for characters with very different power levels to work together without one overshadowing the other.