[sjackso]

A local hobby shop sold a kit with ten bits, 1.0mm down to 0.1mm, which I bought on a lark several years ago.

The middle sized bits are occasionally useful to (carefully!) finger-drill a tiny hole through a plastic part. They're rigid, very sharp, but pretty breakable if you're not careful.

The 0.1mm bit is so small that it's upsetting even to look at. I've never taken it out of the case.