There is basicaly only one riff in this song and it is divided into 2 variations.
I am absolutely positive this is 100% correct because i took it from the live dvd. 

If you wanna get the effect that Reznor uses on the CD you can turn your bass down a little and your treble up a little. Play the song almost like your popping it. Play the note much harder than your used to (just do break a string). Not too much or i will regret ever telling you to do this.

G|-----------------------------|----------------------------||
D|-0h10-11-12p0--10-11-12-0--3-|-0h10-11-12--10-11-12-0--3--||
A|-----------------------------|----------------------------||
E|-----------------------------|----------------------------||
           Variation 1                  Variation 2