easy, same technique as the hacksaw, but using dremel. miles faster..
<touches wood> 21years of mtb & never had a seized seatpost.. ounce of prevention & all that
think of the daddy of hobbyist tools... on steroids. Lots of miniture cutting discs/grinding tools/polishing wheels etc.
This was a MAJOR cash cow for my previous employer Bosch.
Good, but in many cases hand tools are quicker and lots more controllable. You get to 'feel' the blade gently working its way in :?
Personally would not use one for this job, too much at stake.
Useful for cutting the top off the post I guess. It'll save you a good 30 seconds over using a hacksaw (not factoring in plugging it into the mains). The main bit of the job as gump suggest is using a hacksaw blade to carfully cut out the remaining post.