I take lots of notes of my thoughts, though I suspect it is mostly due to my obsessive nature and fear that I could forget an important thought.
The thing is, when will I take the time to go through the thoughts? I have a text file with over 10k lines of notes. It's a question of opportunity cost, I could wade through my old notes or do something else.
Related to: Living Luminously
Well? Should you?
Linked is a treatise on exactly this concept. If the effects of recording and classifying every thought pan out like the author says they'll pan out... well, read a (limited) excerpt (from the Introduction), and I'll let you decide whether it's worth your time.
The full text is written in a stream-of-consciousness style, which is why I hesitated to post this topic in the first place. But there are probably note-taking junkies, or luminosity junkies, or otherwise interested folk amongst LW. So why not?
(Incidentally I'm reminded of Buckminster Fuller's Dymaxion Chronofile. I wonder how he managed it, or what benefits/costs it wrought?)