Using CNC mill to engrave

Hmmm...
The post about dental drills got me to thinking..... My mom was a dentist
and as a kid I used to have the old mechanical (belt) drill she had while
in school. It was *great* for hobbies (model aircraft, etc). The modern
ones are all turbine and turn around 300K at full torque; this is obtained
by using 11 different stages in the turbine. It is no wonder they whine so
much... but they only use about 30PSI or so. Amazingly, however, they are
not that expensive. You can get a head for $250 or so. I imagine that
they must run pretty darned smooth too or it would hurt like hell (wait...
it DOES hurt!). The bits are usually carbide or diamond, I believe, and I
wonder how they would work for the type of work (engraving, PCB routing,
etc) we are talking about.

Please excuse me if this group has already covered the dental handpiece
usage....
--Alan