Can't think of any other. However, Final Fantasy games are only sequels by name, the games aren't really sequels at all (apart from X-2 but that was crap).
Could well be the Madden series or FIFA, if they count...
If you want sequels you only need to look at EA Games and FIFA, there has been a sequel/update every year since they started, there are a few Collin McRay Rally's out there and Golf games that have "evolved" over the years, but I can't give you a specific number of versions of FIFA since the "486" days as I was never interested in any of them!
The Might and Magic series also has many titles - 9 I think, as well as four "Heroes of Might and Magic" games. Final Fantasy has 12 numbered titles as well as "Final Fantasy Adventure" which was released on the Game Boy, also a Chocobo racing game only ever released in Japan (I think). Final Fantasy VII will soon have some companion games released - "Before Crisis" and "Dirge of Cerberus", as well as the CG Movie "Final Fantasy VII - Advent Children" which is a direct sequel to the game.