I occasionally go on 2-4+ week treks, often to places without a power source (or with limited time at a power source). I have a Pentax K200D which accepts AA (I use and carry a lot of lithium AA) and is very energy efficient. However, I'm almost exclusively using the m4/3 camera now (an EP-2) and I'm tired of carrying around the weight of the Pentax. I'm also in the military, which often brings up the power problem, plus (I'm not Combat Camera) also means that even the Pentax does not get taken along. How would I be able to take the camera with me and keep it powered up? I take a good amount of photographs and video and also use the electronic viewfinder. Does anybody have any experience with this problem, either with m4/3 or non AA dSLRs in general?