To keep up my programming skills, I've written a program to calculate gravities and estimate final abv based on the ingredients. It works in either English or metric scales, and in SG units or degrees Plato. On a second page, it can also do hydrometer reading temperature corrections for hydrometers calibrated for either 15 or 20 deg C (60 or 68 F). I'd be happy to make this program, and/or the source code available to anyone who wants it. At this point, it should be considered beta software - there may yet be bugs I haven't discovered. It was written in Delphi Pascal and has been ported to Lazarus Pascal thus both a Windows and a Linux version is available. Below are screenshot of the two pages. If anybody is interested, please let me know and I can either email the program or send it via Dropbox.