Frugal Woodworking

This idea comes from Jimthecarver at Lumberjocks.  He uses self-adhesive sandpaper on old battery operated tooth brushes.

Some of these toothbrushes have rotationally oscillating heads and some oscillate front to back.  Either way, they can be a useful tool for sanding in tight spaces.

This is a great example of re-using and re-purposing a tool.  When they get too scuzzy to be used on your teeth anymore, trim the bristles off with a knife or razor blade, then stick the sandpaper down to one of the moving parts.   To add a bit of control, it is best to epoxy a piece  shaped wood or plastic to one of the moving parts.  That way the sandpaper is fully supported.

Many of the toothbrushes have exchangeable heads so you can prepare a few different shapes that suit your detail sanding needs.

There are a couple of tutorials on making similar toothbrush detail sanders, this one using double sided tape and this one using sanding sponge.