One of the more interesting battery designs we've seen in some time, iWalk's new Link 5200i ($75) combines a power source and a stand into one accessory. Shaped like an extruded triangle, it can charge equipped devices directly thanks to a plug hidden under a cap at the top. There's also a full-sized USB port on one edge, and a Micro-USB port on the opposite side, plus a slide-out tray for holding devices charging with a self-provided cable. iWalk…