PDO has announced that it is now shipping its Sleek Crystal Case and Sleeve Leather Case for the fourth-generation iPod nano. The Sleek is a two-piece snap-together hard case made of clear polycarbonate, and features integrated screen protection, included screen and Click Wheel film protectors, and open access to all ports and control. The Sleek Crystal Case for iPod nano 4G sells for $20. PDO’s Sleeve Leather Case for iPod nano 4G is a form-fitting black leather case featuring velvet interior lining, color-matching stitching, included screen and Click Wheel film protectors, and open access to the screen and all ports and controls. It also sells for $20.