The Fuelank Uno does exactly what it says it does: charge one device at a time. And with the Callpod's adapter tips, it can charge one of a lot of things at a time.
Affordable and useful.
The Uno is portable—a lot more portable than the original Fueltank, which charged two things simultaneously. The bonus of not having two is that you can actually pocket this one, if you're the kind of person who really needs to make sure your devices are powered.
Other than the fact that it's smaller, lighter and more discreet than the Fueltank, there isn't a whole lot of difference. We shoved a bunch of our gadgets into it and the Uno charged all of them fine. You even get 2 tips (an iPod one and a mini USB one) for free. The only downside is that it's give-or-take about half the capacity of the regular Fueltank, which isn't that much larger. It's just larger enough that you wouldn't want to pants it.
For $40, the Fultank Uno is a pretty cheap safety net for the times when you forget to charge your phone. [Callpod]
Compact enough to carry with you all the time
Uses Callpod's many tips, so you should be able to find one for your phone or device
Doesn't hold as much charge as its bigger brother, the Fueltank