My folks gave me a pretty nifty Dremel kit for my birthday, which included about 20 of those little flat sanding discs (probably about 300-400 grit range). Man, those little things are handy for taking off rust and tarnish!

As long as I'm careful which way the part of the disc close to the edge is spinning, they work wonders. They don't take off very much metal at all (I occasionally find myself wishing they took metal off a little faster) and once they start to get worn out a little they actually provide some polishing effect.

I usually get about 1 razor per disc or so, more or less depending on the amount of really gross material that needs to be gotten rid of, and how careful I am to make sure that the disc is spinning away from the edge.

Just thought this might be helpful to somebody. I know the sanding drums you have to be _very_ careful not to take off too much material, and these discs conform themselves fairly well to hollowed blades.