Without a doubt, OtterBox's Defender Series Case ($90) is the most rugged and protective we have seen for the iPad 2 -- though still not watertight like the company's highest-end designs for other devices. Composed of three layers, it certainly adds some bulk, but fans of Otterbox's cases won't mind that: a hard plastic case clips around the front and back of the device with cutouts for all of the ports and buttons, with a large opening around and…
