At last, this simple CNC spindle I (speculatively) knew was possible.
It simply consists of 3 skate bearings, a collet holder (with an 8mm shaft) and one piece of machined metal.
The collet holder can be had for just $10, and I already have the bearings, just need some aluminum and (or brass) and a pulley.
Too bad the collets are Pricey $$$.
Links and Pics.. Here