Dwarf Fortress, in my opinion, is a contender for the best game ever made. No graphics to speak of, but the gameplay is rich and deep. It starts out like an oregon trail type game, then transitions into a sim-dungeon and ends as an empire management game. It has a lot of micromanagement, but the ability to automate is second to none. The learning curve is brutally steep and the interface is barbaric, but the game itself is well worth the price of admission. It's free, so take a look if you haven't already.
I also just bought Elven Legacy which is sort of a modern Fantasy General style of game. It's fun but it crashes on me occassionally. Not a big deal since it's turn bsaed and autosaves, but still disappointing.
