Well, in case you had a currupted harddrive, then it would be nice with some form of backup..
Why on earth would I backup anything? That's just a terrible waste of space. Linux doesn't crash, last time I checked, so it's not like I'm going to BSOD and lose all my files like that one fateful (windows using) morning...
Besides, if you just tarred everything and kept it on the same disk, that wouldn't do you any good. A backup is only useful if it doesn't get destroyed along with the regular files *-- and I don't have anything buy my HD to store it on
I usualy have a second comp. on the net, where I rsync the /home to make sure the users allways will have their files..
Oh and it's through ssh, so no security holes either..
rsync -az -e ssh /home my_backup_machine:/backup