Watch the Math Rock Shuffle Two online guitar lesson by Angus Clark from Hard Rock Survival Guide: Rhythm
A compositional element to look at in this example is how the 6/8 riff gets moved across string sets and up the neck. This is one of those classic moves you find in rock tunes where a bluesy lick gets moved around with no regard for what key you are in. Because the notes of the riff are always the same in relation to each other, the lick drags the listener's ear through the parts where it's outside the key. This is a fun way to write riff based parts of songs, it's not very book-ish but it can yield really intriguing results.