this is a fun thread. I wanna get a centrifugal supercharger and see if i can make a CVT style gearbox (modified snowblower belt drive maybe) to drive it. 
i already have homemade centrifugal supercharger project that i started in HS (11 years ago lol) and never finished. I found some bearings (ceramic) that could take the loads and speeds im looking at but i could never find the compressor map for the turbo that i was using. guess ill have to guess.
Brian