The drills Toolmanmike speaks of can be re-sharpened (all drills can be re-sharpened), but I doubt you will find anywhere to re-sharpen them at a reasonable cost (vs buying a new drill). Unless you have a machine to drill on (lathe, mill or drill press), I wouldn't bother with the M42 cobalt tool steel drills, as they are very brittle, and are more than likely to break off in the part you are drilling with a hand drill.
