Having enough power to get through the day is a constant issue for people who use their mobile devices a lot. Battery technology has come a long way, but we're not quite at the Star Trek level yet where those tricorders seem to run off the air itself. Spare batteries is an option on some devices, while external batteries can be the solution for other. A Kickstarter project called JuiceTank however takes a different approach by making sure your charger is always with you – at least for US based iPhone users.
The way it does this is by embedding the entire charger in a case. The naturally somehwat thick case has a flip-out US plug built right into the case itself, so that when you run low, you simply find an outlet and plug the entire thing in. No cables, no bulky chargers, simply plug in the entire phone.
While I couldn't see myself using something like this myself (not being in the US and not having an iPhone aside), I think it's a great idea that would be perfect in many situations. Especially if you use a Bluetooth headset perhaps, since this would make the phone rather difficult to use while charging. The project is trying to raise $125,000 to get this made and is currently at only $25,000 though, with 54 days left, so if you're interested you might want to put your money where you mouth is sooner rather than later. Kickstarter is often a place where projects with high goals don't get funded while projects with lower goals raise much more than they hoped for.[Kickstarter]