> Keep a record of "stupid errors that took me more than 1 hour to solve"

I’ve been doing this for the last three years, but electronically, and it’s amazing. In my home folder there’s a giant text file that’s like my personal log file. It gets a new line at least once an hour, when cron pops up a box and I type in what I’m working on. And for those times when I’m working on stuff that’s perplexing, I write to it as a stream of consciousness — “tried this, didn’t work” “wonder if it could be due to xyz” “yep, that was it.”

I’ve used it a few dozen times to either look up how I solved a weird problem, or why I decided to do something a certain way. I’ve even built pie charts of how I spent my time in the last quarter by sampling it Monte Carlo style.