A new album called "The Downward Spiral" came out in 1994. It is the most popular and famous Nine Inch Nails album. Music stores have sold more than 4 million copies of "The Downward Spiral" all together. The songs "Closer", "March Of The Pigs", and "Hurt" were very popular on MTV and radio stations. Trent Reznor asked many other musicians to make remixes from the songs. The remixes were released on a new album called "Further Down The Spiral".