GoodSync - GoodSync provides highly reliable file backup and synchronization for both individuals and businesses.
Veeam Backup - Backup and restore VMware and Hyper-V virtual machines with Veeam Backup Free Edition. Unlimited hosts and VMs. Free forever.
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.
Zerto - Virtual replication & recovery solution
Syncthing - Syncthing replaces proprietary sync and cloud services with something open, trustworthy and...
SolarWinds Backup - Modern server backup software