I just ran iDefrag on my iPod and lets just say...wow. it was really fragmented but this was taken care of. Now im curious and would love to run this on my main HDD However, iDefrag refuses, saying it can't unmount the main drive and i should run it from another drive or CD. I don't have another drive nor do i have a bootable CD so i was wondering, if there is a way to run it (iDefrag) on my main HDD? Edit: By the way before any of you start preaching, i know OS X doesn't need defragging like windows does but i also know the built in OS X optimizer could do with a helping hand. So, i WANT to run this.