For the series of videos I made for NOCTUM eyewear, I built a rotating turntable to use for Snaredrum Steve, who's an Iraq War veteran. In concept video Steve plays drums as the scenery around him evolves.
 I cut out 2 sheets of 1/4" plywood and added supports with 12 swivel casters. When I threw out my old green screen treadmill, I saved the motor and belts and mounted them to a wood base. I shortened wiring for the control board as well. I was able to maintain enough torque to spin the turntable with a few hundred pounds no problem. 
We shot at Manifest Media where Mike, the owner, let me utilize the 40' green wall. The only real issue I had was pulling a clean key from the footage because of the green reflection on the cymbals. The next turntable I build will have an aluminum frame and sit on top of bearings for quieter operation, which will come in handy for all sorts of visuals and effects. The finished shot below, was composited in After Effects using Element 3D.