MyCharge -- the same company behind PowerBag, including Instant Messenger -- has recently introduced a new line of battery packs for iOS devices. Just ahead of Apple's expected replacement of the classic 30-pin Dock Connector, we received four for review: Sojourn 1000 ($40), Trek 2000 ($60), Summit 3000 ($80), and Peak 6000 ($100). All are self-contained and require no extra cords or cables; Dock Connector plugs and USB cables are built right in.…
