I have a first generation iPhone and like it a lot. One of the worst things about it though is that if you watch many videos on it the battery drains very quickly, iPod owners have this same problem. This fact has led to the proliferation of back up batteries for the iPhone and the iPod. Some batteries are only for the iPhone like the iPhoneck we talked about before.

If you want something a bit more universal that will work for your iPhone, the iPhone 3G coming this week and your 30-pin connector iPod, i.Sound has the battery for you. Called simply the i.Sound Back Up Battery the little device is a 2-in-1 charger that can charge your phone and the internal battery at the same time.

The battery promises an additional 30 hours of music playback, an additional 6 hours of video and an additional 3 hours of talk time. The battery also ships with a retractable USB charging cable and a USB AC adapter for times when a PC isn’t available. LEDs on the front of the battery make it easy to tell how much juice is left. The i.Sound Back Up Battery is available now for $49.99.

i.Sound