Keep on talking, keep on rocking-
Kensington Mini Battery Extender and Charger for iPod; iPhone 1G, 3G (Black) has the power you need to keep the conversations and music going .

Power and charge your iPhone or iPod on-the-go, and enjoy an extended playtime of up to 30 hours of music; 6 hours of video; or 3 hours of talk. The high-capacity, rechargeable Lithium-Ion Polymer battery pack is small and unobtrusive enough to keep connected to your iPhone or iPod while you’re using it.
You can keep using your iPhone and listening to music etc while this is attached (it puts it into charging mode like plugging it into a wall outlet). It works for iPhone 3G for sure.

The LED battery meter lets you visualize how much juice you have left, and the included retractable USB charging cable makes powering up the battery pack a snap. Backed by Kensington’s 1-year warranty.

Product Features

• Compatibility: iPod nano 1G, 2G, 3G; iPod classic 4G, 5G, 5.5G, 6G; iPod touch; iPhone
• Power and charge your iPhone or iPod–extends play time up to 30 hours of music or 6 hours of video (on iPod nano 3G) or 3 hours of talk (on iPhone)
• Includes retractable USB charging cable
• High-capacity, rechargeable Lithium-Ion polymer battery pack for increased energy efficiency
• Small enough to keep connected to your iPhone or iPod

What’s in the Box
Kensington Mini Battery Extender and Charger for iPhone and iPod (Black), USB charging cable

You ca buy this at:
Kensington Mini Battery Extender and Charger for iPod; iPhone 1G, 3G (Black)