A little over 20 years ago, the folks at Accolade created a simple, elegant, not to mention fairly challenging puzzle game. They called it Ishido: the Way of Stones.

It was one of two games of that period to contain an implementation of the I Ching -- the other was called Synchronicity and was not so much a game as a multimedia version of the Book of Changes. (Interestingly, the creator of that software produced another version of the same concept, called: I Ching Online. Sadly, the link to the oracle on the webpage is broken.)

Ishido is much beloved by both gamers and its creators. Ian Gilman, who did much of the game's programming at the age of 17 (and went on to found enterprises like Live365, has a webpage devoted to the game, which includes free downloadable versions for the PC and (older) Macs, as well as an online Javascript implementation.

Try it out and let me know what you think! I'm going to spend at least a part of my weekend hunting for 4-ways.