This is an abstract strategy game played with dice and a chess board. You are trying to move your dice across the chess board (in a fixed zig-zag pattern) before your opponent has move their dice across the board in the opposite pattern. The twist comes that after you have rolled and moved a die (which can be your own OR an opponents), it is placed on the board with the rolled number up, and if you land on a die, you move again based on the number showing, but forwards if it is your opponents die, but backwards if your own.
It has feeling of inspiration from a lot of traditional/classic board/chase games, including (obviously) Ur, but also Backgammon and Parcheesi.
Full rules at http://www.luchacabra.com/?p=53
Play online against human opponents at http://www.ethnoludie.com