Duplicati - Free, Encrypted Offsite Backup
Duplicati is a free/open-source application available for windows/linux/mac that backs up to ftp/sftp/google drive and many other cloud storage provider. The backups are encrypted using AEScrypt and a passcode of your choosing. So instead of purchasing backup software you can use this for free if you have your own storage already in google drive/backblaze/amazons3 or in my case an offsite server via sftp.
Alternative to services like crashplan/carbonite/etc.