iGadget Life posted a review on the iPhone 3GS / 3G Dock and External Battery Pack
A quote from the article:
>> iPhone 3GS / 3G Dock and External Battery Pack Review
For today's review, the folks at MobileFun sent over the iPhone 3GS / 3
G Dock and External Battery Pack which features a double dock and comes with an external battery. The dock can simultaneously charge both the iPhone and the external battery pack or two iPhones at once.
>> iPhone 3GS / 3G Dock and External Battery Pack Review