Been looking for something for some time now.  Saw this item at Harbor Freight.

http://www.harborfreight.com/3-inch-pneumatic-polisher-kit-99934.html

For $30 (what I paid in the local store) thought I'd give it a try, fully expecting it to be too fast / aggressive for model work.  
I was sure I would try it out and end up returning it.  

But, its a keeper.    

Small and compact enough for easy control, weighs about 1.75 lb.  It has a built in speed valve, and by using that and regulating air supply down to 40psi, you can get the rpm down around 100~200, and it maintains the torque so it doesnt stall out.  Has 2 different foam pads and a wool pad, all velcro attachment.  Those are also available as a seperate kit. ($12 in my store).  I use rubbing compound with the coarse pad, polishing compound with the fine pad, and swirl remover with the wool pad.  Works great.

I will soon have one of these, Allan!  Thanks for the tip.  (Should also work well on instruments! )
Will