http://www.redrok.com/led3xassm.htm They have a great little single axis circuit to power a motor to keep the panels pointed right at the sun all day. I have the motor (satellite dish linear actuator) and enough steel lying around to do the project. Sells in kit form for only $20 or fully assembled for $35. One nice extra in this circuit is that when the sun goes down - the panels will turn back to the east and park there, waiting for the sun to come up the next day. If all goes well, I might have to try their dual axis circuit to drive that new solar oven I started over a year ago and have yet to finish.