I just saw this on engadget.
http://www.engadget.com/2010/10/19/k...sp02-e-reader/
I have been wondering why ebooks haven't started putting solar power cells on them before. Their power requirements are low enough that they could either significantly extend the battery life or replace recharging all together. Imagine, while your ebook reader sleeps during the day, it automatically recharges without you having to do anything so it is ready for hours and hours of reading that night

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Bill