Dremel 8050-N/18 | $68 | Amazon
You might not need to use a Dremel all that often, but it’s one of those things everyone should keep in their tool box, if only for sanding wood and carving jack-o-lanterns, and this compact battery-operated model is marked down to $68 today on Amazon. There are cheaper corded models out there, but this thing is small enough for one-handed use, and it even comes with a docking station to keep the battery topped off.