I actually founded a company some years ago that used this exact technology to make advertising displays. We had 72 RGB LED's on a spinning circuitboard, and mo

I actually founded a company some years ago that used this exact technology to make advertising displays. We had 72 RGB LED's on a spinning circuitboard, and modulated the red green and blue so that we were able to create full-color. This was enough to display pictures in reasonable resolution. One of the hard parts was getting power to the circuitboard with the LED's, the standard solution would be a brush of some kind but this proved to be too shortlived and needed a lot of maintenance because it broke. We ended up using some voodo with induction and magnetism so that we sould transfer power wirelessly. I've long since left the company to go on doing other things, but I still dream of using this technology to make a globe (the spinning circuitboard reaching in an arc from north to southpole and revolving around the north/south pole axis) that would be connected to the Internet so it could show live weather, Google maps, or where your global fleet of submarines are stationed at this very moment. We even developed and patented a touch-sensitive technology to go with the display so that you would have an interface to the globe. (you would probably need to put the rotating part in a glass globe unless you want your hands slapped pretty badly) If any hardware hackers out there that are interested I might be able to dig up the technology. Won't promise anything though.