I was thinking of creating a large solar panel composed of maybe 40 or so of these
http://www.solarbotics.com/products/scpd/
then mounting them along with some light sensors onto a moveable panel which would which would adjust based on the readins of the light sensors to allow maximum sunlight for the solar cells. You could then add capacitors to store the energy for the motor/ sensors ect. while diverting the remaining energy to whatever you like. e.g. 9V battery charger, direct power for robot, you name it.
This would seem like a very usefull/ fun project as well as help to learn more about programming/wiring. Im still in the process of building my start here robot so i wouldnt expect this to come from me for a few months but i would love to hear your guys ideas about this. Any feedback or recommendations you have would be great, as well as any sites/ books where i could learn more about making PCB required in projects.