I don't entirely understand the mechanics behind "Mr. Fix It" Rick's "Magnetic Tesla CD Turbine," but it's clear that it's a cheap way to reuse CDs to make a crazy whirring spinning thing. (So much so that he can spin it fast enough to shred the discs, although you certainly wouldn't want to do that without all due safety precautions.)
If you find the above video intriguing, Rick's got several videos up on YouTube explaining how the system works. The turbine doesn't always have a Skilsaw blade attached, but that is clearly when it is operating at maximum awesome. (Putting the "rad" in "radial?")
Rick tells us:
I have more plans in the making for the CD Turbine such as a stacking feature, where two or more CD Turbines can be stacked together, linked magnetically. Also, a CD Turbine Generator that runs on garden hose pressure (It's already got rotating magnets...). I'm also going to hook up an auto alternator to the air version...it should work to charge a battery. I will also be making a similar CD design as a pump (Tesla CD Pump: hand, drill, water or air powered!).
Tesla CD Turbine with Skilsaw Attachment [YouTube]