You pretty much need a second, similar system, hopefully not physically nearby. Tape doesn't scale down to home use, and optical is too small. My home NAS has

You pretty much need a second, similar system, hopefully not physically nearby. Tape doesn't scale down to home use, and optical is too small. My home NAS has several roles, so I don't have to backup the full capacity. The family shared drive definitely needs to be backed up. The windows desktop backups probably don't, although if I had a better plan for offsite backups, I would probably include desktop backups in that. TV recordings and ripped optical discs don't need to be backed up for me, I could re-rip them and they're typically commercially available if I had a total loss; not worth the expense to host a copy of that offsite, too; IMHO. You might do something like mirrored disks on the NAS and single copy on the backup as a cost saver, but that comes with risks too.