Just be careful of where you leave it. Where I live, the temperature can go below freezing and kill the LiON battery.
The unit is widely available under a number of names. "Go" comes to mind.
I saw an interesting gadget on ebay. Has anyone used a Lithium ion powerpack? It available for a variety of different cameras. It is rechargable, with a car adapter and an ac adapter and has a 5 year warranty. Has anyone used one of these? What did you think?