Here's an idea: A little book of photgraphy tips that you can hook onto your camera bag for hints on the go!
I've created exactly that! Little Tips: The Take-Along Photography Booklet is a set of 10 laminated cards with more than 75 hints to improve your photography. It is small and super-light, so you can add it to your gear and use it wherever you take pictures. At a special introductory offer of $5.75USD ($7.75 after Feb. 5th), it is also super-cheap! Now you can bring all those ideas with you! I wish I had had one of these myself when I was starting out.