Here's a 'set it and forget it' backup system which might look rather familiar to the backup solution supplied with a certain well-known fruit based computer.It comes with a configuration interface for KDE's plasma desktop, but it will run on anything else if you're prepared to do some config yourself. Please see the WIKI for installation instructions
Thanks to Mike Vaughn, there is now an Ubuntu PPA for installing TARDIS:
https://launchpad.net/~mikevaughn/+archive/omnilinux/