This might be a long shot, but a year or so ago AT&T stores carried a rechargeable USB battery pack that had a built in AC plug and dual USB ports. I should have bought one at the time because it doesn't look like they carry them in store any longer. As a matter of fact, I think they had been $50.00 and were clearanced out at $20.00. I think they were manufactured by Targus, Kensington, or some similar company. Anyway, does anybody happen to have a way to identify this better so I can buy one of these? I have tried Ebay and Googling this, but I am not coming up with what I want.
The other option would be if any other company makes a rechargeable battery pack with dual USB ports and a built in AC plug, I would certainly consider it.