Intro bass riff, low E string:
E|-3-2-3-2-3-2-3-2-3-2-3-2-3-2-3-2-|

Verse Riff:
B5 G5 C5 F#5

Chorus Riff:
C5 D5 G5 (The D5 is only for about a beat right before the G5)

Post-Chorus (It's no fun!):
F5 G5 
for this bit I like to use 4 string power chords higher on the neck like so:

     F5         G5
E|--------------------------|
B|--------------------------|
G|---10---------12----------|
D|---10---------12----------|
A|---8----------10----------|
E|---8----------10----------|