I've been leaning more and more towards setting up a track-everything tool myself. Mood, food, pains, sleep, weather, productivity measures, literally anything I can come up with. Combine that with a prevalent keylogger which also tracks applications, and I could build up some huge statistics on myself, and maybe find causes of problems (and I'd just be interested).
Of course, part of the fun of making it myself would be experimenting with ways of representing and extracting meaningful information. I haven't brainstormed on it much; so far I'm at "dump it in SQL" because I can build a query for just about anything really quickly.
