Hack a day shows how to make a mini USB charger using a standard 9 volt battery
This is not cool, it's a life saver for geeks. More and more of the latest gadgets can be charged via USB and a mini pocket charger that works with a standard 9 volt battery is just coolissimo!
You have to be familiar with a soldering iron or know someone willing to make one for you (Mike, are you reading this :-)