rocknroll (Rsync fOr baCKup and Roll) is an incremental backup maker based on rsync. It backs up a remote directory tree to a destination directory on the local host. For this backup, it manages a set of archives named tag.1, tag.2, etc. Using the famous "link-dest" option of rsync, it keeps only the difference between the different archives.
Pylsyncd is a Python implementation, similar to lsyncd, that uses rsync to synchronize local directories with several remote machines running rsyncd. Pylsyncd recursively monitors a set of directories using pyinotify, a pure Python module used for monitoring filesystems changes that relies on inotify. The main advantage of pylsyncd against lsyncd is that it uses message queues in order to synchronize several destination servers in parallel, saving up time when it is required to have more than one destination. It has been tested in heavily loaded environments.
Beaver is a simple concurrent backup system with snapshotting. It is based on a simple list of servers, a file of configuration options, and lists of things to be excluded or included. More powerful configuration options are available in the configuration files. Different copies of beaver backup can be run on the same server with different configuration files. Beaver backup is normally run by cron on a central backup box and uses keychain for remote authentication.