Castle Danger is a turn-based, abstract strategy game, in that way like chess. It is also like chess in that it is a perfect knowledge game, with no element of random chance.
Check out http://www.mwgames.com
There is a table-top version available for purchase, and a freeware PC version. The PC version has no AI opponent, but it supports netplay and PBEM (via the save-game feature).
I think the game pretty much rocks. It won't replace chess for me, but it is cool.
I'd love to discuss strategy and/or play someone...
Also see http://www.boardgamegeek.com/game/6995
Especially, there is an article there by the designer of the game.