I hear mixed suggestions on running scandisk and diskdefrag. On one side of the fence, I'm hearing to run scandisk often, even the "thorough", about once a week, before running diskdefrag. Others say, run scandisk only when it's needed( ie, you can't get through disk defrag), because it's hard on the drive. Still others say, you rarely need to run either, if you have a large harddisk. I would think the truth lies somewhere in the middle. What is a good suggestion, on running scandisk and diskdefrag, say, on a 40gb size harddrive, that maybe has less than 10gb of space taken, and, the computer gets average use time?