For OS X, backup solutions that perform just like Time Machine?

"If you're looking for a way to back up OS X to say, another file server system than a ""time machine capsule"", you can backup time machine to a linux system running AFP via netatalk. The information on doing this is a bit spread out and disorganized in general, and since I'm not a blogger, I haven't put it together in a coherent way. Here's a general overview, and some sites that I used to set it up on an Ubuntu 9.04 server.

Rebuild the netatalk package to encrypt authentication. Leopard requires this, but its not enabled on Debian/Ubuntu by default.
Set up the volumes you want to share on the server and start the netatalk service.
Disable the strict checking for Time Machine volumes on OS X. I don't recall the specific command, but this is easy to find.
Create a sparsebundle file with the HD Util, and copy to the server.
Tell Time Machine to connect to the server.

http://www.kremalicious.com/2008/06/ubuntu-as-mac-file-server-and-time-machine-volume/

http://blog.damontimm.com/how-to-install-netatalk-afp-on-ubuntu-with-encrypted-authentication/

http://holyarmydotorg/benjamin/2008/01/time-machine-backup-to-linux-via-netatalk/"

"A bit of a side note, but as the way to restore data might be as important as the way to backup:

Time Machine not only integrates well with the OS, but also with Time Machine-aware applications like Mail, Address Book and iPhoto. When entering Time Machine while one of these applications is active, you'll see the regular star field with that application (rather than the normal Finder).

This even makes it easy to restore messages from email accounts that you've deleted altogether, without the need to know how Mail uses the file system."

BackupPC and rdiff-backup both store incremental backups. BackupPC comes with a web interface and uses hard links like Time Machine, but is not straightforward to install on OS X, compared to Linux where it's packaged for most distros. rdiff-backup stores deltas instead of entire files, but it's a bit more bare-bones, and you have to install the web interface separately. BackupPC is written in Perl, rdiff-backup is Python, neither has OS X integration.