Three new $20 "Shell" series cases from DLO for the third-generation iPod nano have appeared, each with a feature that distinguishes it from the others. The standard Shell is a completely clear two-piece hard plastic case for the nano, which covers everything but the device's Click Wheel and bottom surface. It's designed to let you see the nano's face color and back with minimal interference. By comparison, MetalShell preserves Shell's back, but replaces…
