SAN FRANCISCO -- Newer Technology Inc. on Tuesday debuted a new version of its miniStack hard drive and FireWire/USB ports add-on for the Mac mini. The remodeled accessory is now available in capacities up to 500GB and features FireWire and USB ports split between its rear and side. Pricing starts at US$139.99 for an 80GB model; an "add your own drive" kit is available for $79.99.