This is going to be a tough one, we know -- our first thought was toward a Powerbag with a 6000mAh battery, but that costs $170, more than twice our man's budget. Is there something cheaper you could suggest to our nomadic friend that'll enable him to stay off the grid long enough to become a modern day Grizzly Adams? All we ask for is a comment, and your knowledge to steer it by."I'm kind of a nomad: I travel anywhere I can, sleeping away from civilization in my sleeping bag. My only issue is that my smartphone needs a recharge every two days. What I need, is an external battery pack that can give me a week's worth of juice -- but can I get a lightweight one that costs under $70? Many Thanks!"