To keep this interesting, I'm going to say top five cause I'm sure most people on this forum have played more than five RPG games, so what are your five favorite character customization system (not to be confused with character creation systems) in which you get to build what type of fighter or mage you're going to party down with.

If you can't think of five specifics, then simply list the five games that had your favorite ones and a little explanation as to why.