Double your iPhone 4′s power with Mophie Juice Pack Air Battery

The Mophie Juice Pack for your iPhone 4 is almost here. The word is that it will be available as soon as next week for $79. The Juice Pack Air features pass-through USB charging and sync with iTunes, an integrated 4 LED charge status, and a standby switch the shuts off the juice turning the appendage into a rather attractive (albeit, heavy with a 1500mAh capacity battery), soft-grip case.  I brought one for a friend last year who had an old iPhone and it worked wonders, so it should be a welcome addition for you iphone 4 users.