i love that song sad but true by metallica, i listen to that when i'm working out sometimes, but outside of that i rarely listen to rock when i'm working out. I do bump luni coleone or lil jon and the east side boyz tho, that gets me amped. Although, on kind of a side note, i've heard that slower music is better while lifting weights due to the fact it promotes herk and jerk type lifting as opposed to controlled slower weight lifting which could save you from hurting yourself, on the other hand, while doing cardiovascular stuff, you should listen to upbeat songs because that does help.