I have several Excel spreadsheets I use for my DIY. Perhaps the most useful is one for all my various experiments. For example, my Chocolate NET project. Each time I tweak it I list the ingredients and percentages. This way I can follow exactly what I have been doing. I add notes below that documents my impressions. Currently I have 8 projects going. I also have a spreadsheet of all the gear I own (well,
mods n atties anyway). Helps plan for the drop dead date. Another spreadsheet I use to calculate recipe tweaks, etc.. Very useful if you know how to use Excel.