You could use Mutants and Masterminds pretty easily for a Dresden Files game, particularly if you use The Book of Magic supplement.  In my opinion, The Book of Magic book has a HEAVY Dresden influence to it as it is.  I am currently running a Mutants and Masterminds right now and it has a HEAVY Dresden influence to it although that was not intended by me.  Four of the five players in the game are big Dresden Files fans (I am the one that introduced them to the books) and three of the characters that have been played were definitely at least partially inspired by the Dresden Files.  We have had a a werewolf, a faerie warrior and a full fledged wizard for characters so far.