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Energizer AP1500 Protective Case w/ Built-in Battery for iPhone 3G/3GS for $12.99 Shipped

Energizer AP1500 Protective Case with Built-in Battery for iPhone 3G/3GS for $12.99 shipped.  Here is a screenshot for your reference.  It features a built-in battery and an LED battery life indicator light, and includes a USB charging cable as well as a free X Games Platinum Snap-on Faceplate for iPhone 4.  Most places have the protective case alone for about $19.