Using TU11, I'm looking for an option that allows me to schedule weekly backups, but ONLY if it can do so without gradually filling up my external drive more and more. In other words, I'm either looking for a way to automatically overwrite my weekly full backup with a completely new one (so it's always using the same amount of HD space, rather than making a second full backup file), or just keep a full backup with ONE incremental file that it overwritten each week. Do Differential Backups allow you to do this? The descriptions of Incremental and Differential backups are confusing... I can't tell if creating Differential backups is going to always overwrite any exiting ones, or just keep piling up new files every time you run TU (as with Incremental backups). I'm assuming there's a way, or else scheduling backups would seem pretty useless if it gradually filled up your drives. 'Need something that's 0-maintenance, and doesn't make me have to always go and delete the obsolete archives.