My family’s solution to this is to use FolderShare and sync directories across our extended network. We all live in different states with cable modems. I sync to my sister, my sister syncs to my dad, my dad syncs to me, etc. This provides the benefits of an offsite storage provider like Carbonite or Amazon without any of the cost or reliance on third parties. If FolderShare wasn’t an option, I would use the Hamachi VPN network we have and something like SyncToy across the same machines.