DIYer Theodore Protasiewicz shows us how to mod a backpack with a few solar panels to charge your devices with the midday sun.
All you need for this project is three solar panels, some soldering skills, and a USB hub. When it's done, you'll be able to plug in your phone, your MP3 player, and anything else that charges via USB and top off its battery as you walk from place to place. It won't necessarily charge as fast as a wall outlet, of course, but if you're always on the go, you might as well get some extra juice out of your walk. Hit the link to see how Theodore put his together.
Solar Panel Backpack [I Am Theodore Protasiewicz]