I'll throw in a good word for King of Dragon Pass. It's an RPG/strategy hybrid, and definitely unlike anything you've played, before--unless you're familiar with KOEI's excellent series of Japanese and Chinese fantasy/historical simulations. (They stopped making the series for the PC roughly ten years ago.)
Basically, you're the head of one small tribe among many in the fantasy land of Glorantha. You have to consider a range of activities including farming, trade, exploration, battle, magic and magical quests, and inter- and intra-tribal relationships. Each of these involve anywhere from a few to several dozen choices at your disposal. The game is turn-based, with two turns per season,and five seasons per year.
At the same time, the game runs a relatively randomized selection of plot activities drawn from 500+ in its database that force you to make decisions. Typically, there are five to six replies to any situation requiring your arbitration, none of which are solely good or bad.
I've been very impressed with this game. Admittedly it's nothing like a dungeon crawl, but it has a drill-down depth and replayability that keeps calling me back. You can find out more about it
here.
