I made a full backup to an external drive a couple of months ago and have been using nightly incremental backups ever since. Do I need to keep all the incremental backs since my full one in order to be able to restore my full system or can just keep one incremental backup plus the original full back enought? If I only need the incremental plus the full why is there such size variablility? Some of my incremtals are 12 gigs and and last nights is only 500 megs. What's the deal with that? Also, is there a way to manage the incremental backups? After a while the fill up my external hard drive. It would be great to be able to just keep a set number of them. Thanks for any help.