Though Just Mobile's aluminum stylus AluPen is literally capable of standing on its own, the company has released a bundle called AluPen + AluCube ($40) that adds a matching cube-shaped desktop stylus holder to the prior stylus and carrying case. AluCube is also made from solid aluminum, and feels quite heavy, using rubber padding to protect the AluPen on top and desk below it. A groove in the bottom center is meant to serve as a cable holder for…