Backblaze - Backblaze's remote backup automatically backs up your data to our secure datacenter.

Restic - Easy: Doing backups should be a frictionless process, otherwise you are tempted to skip it.

CrashPlan - CrashPlan for Small Business backup software offers the best way to back up and store business & enterprise data securely - offsite, onsite & online in the Cloud.

Duplicati - Free backup software to store backups online with strong encryption. Works with FTP, SSH, WebDAV, OneDrive, Amazon S3, Google Drive and many others.

ManageWP - ManageWP is a service for bloggers, site owners and web based companies helping them manage multiple WordPress sites from one dashboard.

rsync - rsync is a file transfer program for Unix systems. rsync uses the "rsync algorithm" which provides a very fast method for bringing remote files into sync.