I know it's been debated adnauseum for years, but I've got debate going on with a fellow geek about just what are the true risks if you fail to defrag regularly (I usually do it once a week, AT LEAST once every 3 wks). I've read before that if left unattended for long enough you can actually damage the system files. As a pro-audio user that uses 250 - 450 Meg wav files over 8 tracks, with realtime FX, it's always been recommended to at least have a separate hard drive, and to defrag VERY often. But our real debate was if it truly damaged sys files if left unattended. I maintain they do.
Tanx,
KC