Macessity has announced Stack On Mi, an aluminum color self-powered USB 2.0 Hub for Mac mini.  Stack On Mi was designed for users who wants to show off their Mac Mini on their desk, with or without other Mac mini enclosures. It is 1″ in height, open top and bottom to allow better air flow for the Mac mini. Stack On Mi’s contour fits that of the Mac mini or other third party’s enclosures, that makes it a perfect desk-resided Mac Mini’s accessory, notes the company. Stack On Mi is priced at US$29.99.