4. Dave Mustaine - The 'Spider Chord'
http://www.youtube.com/watch?v=g2z63HdLdy8 Okay okay it's a chord not a riff, but it's just as brain-ticklingly annoying as when your fingers refuse to do what they're told. Mustaine is one of the greatest shredders on the planet, and regardless of how naff latest album Super Collider was, back in the day when he was fuelled by a righteous need to outdo Metallica at everything, utilisations of crazy techniques such as this are what still define him as an incredible musician. When your fingers eventually take on shapes that Spock would look puzzled at, feel free to move on, yet it must be said playing around with this new hybrid chord shape is a great way of speeding up chord changes in any of the standard tunings.