CaliperTool for PalmOS (Freeware)
Since I bought a lathe and have started doing some metalwork I have found myself spending a lot of time measuring a piece and then trying to convert the measurement from thousandths of an inch to fractional inches - usually to find a drill bit.
I wrote CaliperTool to help. Enter a decimal inch value and press "calc." CaliperTool will find the closest 1/64" values above and below your measurement and print them along with their respective errors.
It will also do a simple metric conversion and list the measurement in millimeters.
And if that weren't enough, if your measurement is reasonably close to a "letter" or "number" drill bit size, it will list the closest of them as well.
Try it. It's free.