I've been playing this MUD for the last 11 years it has a very small limited player base but it very detailed and elaborate and contains a mini map as well as crafting skills! You have the ability to create your own weapons and armor from a variety of metals each with their own unique properties and abilities to withhold magic. This game has provided me many years of entertainment and their have been some EPIC stories throughout it's history. There is a very detailed religious and PK system with some unique clans. It is worth trying out.
I played Adventures Unlimited quite a lot during high school and college as Guion. That was a good decade ago or something. I always enjoyed it and stop back in every now and then. I doubt I'll ever be a serious MUDder again, but I probably invested more time in AU than any of the others I tried.