This is a very nice idea. So far I just have a record by digital photographs, of the progress of each quilt, because I take lots of photos during the design process, to help with decisions. I should probably learn to back up my computer. I haven't organized these photos in a special folder, they just appear in my pictures folder according to date.
One thing I thought would be nice, would be to keep track of what audiobooks I listened to while making each quilt. I currently jot down a note about the day's progress in my daily calendar, and sometimes what book I have in progress, but I haven't done anything about organizing all this info into a notebook or computer folder.