Alright, so I'm working on a project, which I won't disclose at this time, and I need as many different ways to generate electricity as possible. Any and all ideas are welcome, nothing is too weird or unconventional. The on requirements are it needs too be portable and smallish, in theory it should be easily carried on say, a hiking trip or something. It also needs to be able, even with some circuitry, to charge a battery. Ideally 2 AA batteries in series, but higher than 3v is OK as well. So, I will compile all the ideas and, if they will work for my purposes, I will include it in my instructable I'm working on. Any suggestions are greatly appreciated and all ideas are welcome. Fire away!