Based upon the award-winning iPhone 4 version but significantly redesigned with softer curves for the iPod touch 4G, Speck's PixelSkin HD ($30) is a flexible plastic case with a distinctive combination of glossy and matte finishes on its grid-styled back -- an evolution of Speck's earlier, chunkier silicone rubber PixelSkin designs. The "HD" version uses a shallower grid with smaller squares, and includes holes for the iPod touch's rear camera, screen,…
