Is there a good affordable solar powered battery charger and is anybody using it? I have recently started using rechargeable batteries for remote controls, cameras, portable music players, etc. Just for fun, I thought I would charge some AA batteries for in the yard lights and use them, thinking I may have saved a penny. Of course that isn't a practical option but it did get me to think about the possibility. I want to be able to charge AA, AAA and speciality batteries that can be charged by USB out from the battery charger. If it exists and the economics are something absurd like it will take 50 years of use to breakeven, I probably won't mess with it even if the value is to the enviroment, not financial.