Today only, Cowboom, a division of Best Buy, is offering the Mophie Juice Pack Air for iPhone 3G/3GS for only $9.99! This product retails for $79, so this is an awesome deal! You’ll only have to pay $5.24 for shipping, so that’s $15.23 shipped.
This case will power your iPhone 3G or 3GS for an additional 4.5 hours! You can also charge this case and your phone at the same time with the included USB cable.