Griffin PowerDock 2

Most docks charge only one device at any one time, but Griffin doubles it's efficiency by offering the PowerDock 2 - this might end up sounding like a sequel, but it is actually able to charge a couple of iPods/iPhones simultaneously instead. Strangely enough, Griffin is also working on a PowerDock 4 - and no, this won't be able to charge a quartet of iPods/iPhones, but goes the extra mile by juicing up half a dozen of such devices instead. You can pick up the Griffin PowerDock 2 for $49.99 while the PowerDock 4 will hit stores this July for $69.99 a pop.

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