This is somewhat unrelated but I must say:
 
You should never, ever, ever have less than 1GB free on any drive at any time unless that drive is under, say, 6GB. Otherwise you are asking for trouble. File systems are designed to require a bit of breathing room. At less than 1GB free on any reasonably recent drive you are going to be fragmenting worse than throwing the drive in a wood chipper. Your performance will suffer. Though... not as bad as if you did throw it in a wood chipper.