Eclipse Solar Gear makes carrying cases for mobile devices. Their cases are unique in they they contain solar panels allowing you to charge your device. Right now they have backpacks, camera bags, bicycle bags, and messenger bags for sale. Unfortunately neither of these is designed to charge a notebook computer.
However, Eclipse will soon be releasing a solar case that charges computers. Bags like this open up great opportunities. How nice is it to be able to be away from electricity and not have to worry about running out of power with your digital camera, camcorder, or notebook computer.
Sure, you may not be worried about working when you are backpacking in the middle of no where. That does not mean you may not want to use your computer to keep a diary or journal. Who knows, you may even be inspired by your location to write the Great American Novel.