ShapeShifter is nice, good suggestion Jaffa, but at the end of the day I do prefer CandyBar. Also, I do not believe ShapeShifter works on the Intel platform yet, if that makes a difference, which I think it might if 7on is trying to run it on his MacBook.
Is there some reason you're looking for an alternative 7on? Is there something about CandyBar that is lacking in features for your needs? Certainly it can't be the $13, as that's very reasonable for such a great little app!