There’s a great online Geography Game called on the “Rethinking Schools” website. I think geography is quite important – especially when you start traveling around.
I’ve even picked up a license for “World of Where“, a similar Mac OS X geography game but it takes too long to start up and my geography for the Americas, Europe and Asia are all pretty well remembered. It’s the Middle East geography that I need a refresher on now and then.
I personally like to just download the Mapgame SWF file directly to my computer and play it via iSwif when I need to relax for a second. Loads a heck of a lot quicker than most games you’ll ever play, and at least it’s useful too!