We have to hand it to Case-Mate for this one: the Stacks Case ($35) is a cool new idea in iPhone protective designs, giving the user the option to customize the colors of a glossy hard plastic frame by using a central mounting rail, one top piece, one bottom piece, and interchangeable central pieces that can be mixed and matched. The three different color packages each come with eight total replaceable pieces; you're limited only by the requirement…
