Dangerously, PowerTrekk hasn't revealed the price of its portable fuel cell/battery back combo charger, but if it's fair I might just have to scoop one up for my next camping trip. Let's hope I never get into the difficult quandary of deciding what to do with my last tablespoon of water—power my gadgets up, or drink to survive.
Connect devices such as your phone, camera, or gaming device by USB to the PowerTrekk, and it uses the PowerPukk fuel packs (sold separately, I'm afraid) and water to power them up. Obviously you don't need to rely on the sun here, making it a good choice for below-ground explorers. Or troglodytes? [PowerTrekk]