Passage: Ghosts I–IV is the sixth studio album by American industrial rock band Nine Inch Nails, released on March 2, 2008 by The Null Corporation. It was the band's first independent release, following their split from longtime label Interscope Records the prior year. The album's production team included Nine Inch Nails frontman Trent Reznor, studio collaborators Atticus Ross and Alan Moulder, and instrumental contributions from Alessandro Cortini, Adrian Belew, and Brian Viglione.
Reznor described the music of Ghosts as "a soundtrack for daydreams", a sentiment echoed by critics, who compared it to the work of Brian Eno and Robert Fripp. The tracks are unnamed, identified only by their track listing and group number, and is an almost entirely instrumental album. Although initially intended to be a five-track EP, the final release consisted of four nine-track EPs, totaling 36 tracks. The album was released under a Creative Commons license (BY-NC-SA) and in a variety of differing packages and price points, including a US$300 "Ultra-Deluxe Limited Edition", without prior announcement. A user-generated "film festival" was also announced, inviting fans to visually interpret the music and post their submissions.
The album received a favorable reception from critics, who complimented its experimental nature and unorthodox release method, although some viewed the former as its weak point. The album reached number 14 in the US, and was nominated for two Grammy Awards (Best Rock Instrumental Performance and Best Box Set or Limited Edition Package) representing the first time music released under a Creative Commons license had been nominated for a Grammy Award.
What was the full name of the album that was compared to the works of Brian Eno and Robert Fripp?