Ars Magica Bundle
It's a rather crunchy system if that's a factor for you but the magic system is excellent and the campaign world is intricate, well researched and quite fun to play.
For anyone who picks up the (very reasonably priced) bundle, there is an Ars Magica discussion group on RPOL that would be happy to help you explore the game and how it works.
In essence, it's a fantasy game as viewed through the lens of 13th century Europe. The focus of play a grouping of wizards who band together in communities of varying size and strength to pursue their dreams of knowledge, wealth, power or other esoteric things wizards want. This community, called a Covenant, is as central a character as any of the players. Events unfold over periods of time as short as the seasons of a year or decades depending on the game focus.