[Rick] has been building Tesla turbines in various ways and posting his projects to youtube. For those who are unfamiliar, a tesla turbine is a fanless turbine that uses a smooth central disk spun by friction from a gas or fluid. Since the turbine itself has no protrusions, it is extremely stable. There are lots of other benefits, which can be explored on the Wikipedia page. [Rick], as you can see from the video above has found several uses for them, from Halloween props, to generators for lights, to an automated shake flashlight shaker, you can even watch him rev one up to destruction. Though most of these are at relatively low speeds, he has shown that he can make one from CD spindles that is stable enough to reach 10,000 RPM. [Rick] admits that all they really do is spin fast and make cool noises, but they do that pretty well.
Update: Moments after this was published, we found an instructable by [Rick] on how to build a blender using a tesla turbine.