Pick.

I'm trying to learn a different way of holding my pick because, no matter how long I practice, my hand cramps up when I'm playing faster and heavier stuff. I gauge my ability from day to day by playing along with "Am I Evil" off the Metallica Garage Days Inc. album. My usual pick holding style, I can only get through a little more than three-quarters of the way before I have to stop and shake out my hand.

Today, with the new style, I was able to get all the way through it. Now I just have to clean up my picking and get a little more used to single string picking and I think I can nail it.

I'll post up some pictures of before and after with how I used to hold a pick and what I did to change it.