Trent Reznor is a free man. In the year since he officially released his last album -- Year Zero -- under contract to Interscope Records, Reznor, 42, developed an Alternate Reality Game built around Year Zero and released a Year Zero remix CD which included a data disc with raw WAV files meant to encourage mass manipulation. He also produced and performed on Saul Williams' excellent free-or-$5 downloadable. Ghosts I-IV is Nine Inch Nails' seventh......