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.
luckyBackup is a powerful, fast, reliable, and fully customizable backup and sync tool. It can backup any directory (the source) to another (the destination). luckyBackup copies over only the changes you've made to the source directory and nothing more, saving a great deal of time for backups after the first one. Whatever changes you make to the source, including adding, moving, deleting, modifying files or directories, will have the same effect on the destination. Owner, group, time stamps, links, and permissions of files are preserved (unless directed otherwise). The synchronization feature works on any pair of directories, keeping the files that were most recently modified on both of them. It includes many safety checks to prevent accidental loss of data.