Evergreen Solar has novel way of producing wafers:

One of the price drivers in solar cell production is the amount of wasted silicon resulting from making square or rectangular cells on a circular wafer. Evergreen Solar creates ribbons of silicon, which are then sliced to length, leaving very little silicon waste (which is probably re-melted and used again). The link below shows a time lapse of the process:

Link (http://www.evergreensolar.com/technology/stringribbon/stringribbon_popup_en.html)