Very interesting. The labor cost of making a small solar panel is higher than that of a large solar panel.
You can buy individual solar cells (not panels, the cells the panels are made of) at very low costs from china:http://www.alibaba.com/product-detail/high-efficiency-156mmx156mm-6-2BB-3BB_1095430687.html
Soldering entire cells together and mounting them is the labor part. But small panels use /part/ of many cells to get to a usable voltage with less surface area (and less current) and so you ALSO have to break the cell apart, and do more soldering.
These guys came up with a better, automated, way to do all that. Very interesting.