The idea behind Dock Extender is a practical one: You have an iPod. Your iPod’s in a case. And you have an existing iPod accessory, such as a Universal Dock-based speaker system or other iPod docking device, that you want to use without removing the iPod from its case. Dock Extender can solve your problem: it’s a five-piece kit consisting of a Dock Connector port extender, a plastic and wire Universal Dock insert, and three rubber pads…