Remember those Labyrinth maze games that were popular about the same time as, oh, say, the Atari 2600? They were wooden and took coordination, so presumably they were educational, but they were pretty fun nonetheless. There is no shortage of Flash descendents of Labyrinth, but the goofily-named Rolley-Ball is one of the better ones, thanks to an interesting little twist in which you can change the color of your ball, which lets you pass through certain walls but makes other walls deadly. Fun stuff, and possibly educational.
Rolley-Ball [Jiggmin]
