I keep my notebooks. I scribble notes in them all the time, and then when I have downtime I look back through them. It&#x27;s great for recapturing ideas, but it&#x27;s also great for avoiding retrodding the same paths again. I am prone to forgetting I&#x27;ve done certain small things before and then I lose time on re-implementing the early parts of it. For example, I&#x27;ve rebooted this one project 4 times without even realizing it: a solar-system wide cross between Moon Lander and Asteroids with a simple, multiplayer mining economy.