expansys offers the refurbished XtremeMac InCharge Duo Charging Base for iPad / iPhone / iPod, model no. IPU-ID2-11, for $29.99. With free shipping, that's $7 under the lowest total price we could find for a new unit. It gives you the ability to charge two devices simultaneously in one dock, including iPads, iPhones, and dockable iPod models.

Note: No warranty information is provided.