I personally backup my entire server daily. It has to be done if you don't want to lose any data in the event of hardware failure or unauthorised access.
Losing a days worth of data would be bad enough so I can't imagine what it would feel like to lose everything.
I have RAID 1 on my work station, and sync up to SVN. As for personal files and movie/music collection, I don't bother with backups at all (Then cry when I realise I have lost those photos from last x-mass, but never learn my lesson).
For personal files (eg. photos, movies) you can use a Deleted Files Recoverer, and there are big changes to get them back (or at least a part) ...of course if we're not talking about a hardware failure (dead HDD).
I back-up most of my server daily to another computer, and important personal photos and files offsite also.