Where do you get your panels? http://www.wholesalesolar.com/solar-panels.html lists prices from about US$3 to about US$10 per watt for panels in the 100-200W range and nothing below 100W, and http://www.solarbuzz.com/Moduleprices.htm has this lovely graph by month up in the US$4.40 range. I see http://www.ecobusinesslinks.com/solar_panels.htm lists some panels for US$1.85 per watt, but the discrepancy is worrying.