Now, I haven't a clue how it works, but Coulheur is a gorgeous colorwheel based clock that is a pretty as it is unreadable. Well, I'm sure you can learn to read it pretty quickly, but it's strange to see.
Meanwhile, iambliss pointed out an online version of Petals around the Roses, a dice puzzle game. The rules are different for the version I learned. In fact, I've got a half finished java applet for the version I learned someplace. Maybe I should brush that up and post it.