After my hard drive failure adventure I bought a second hard drive for the sole purpose of backing up a complete copy of everything via rsnapshot. I was worried it'd be too slow for my 165 gigs of crap, but it's not too bad even on my not-terribly-fast IDE disks.
The first backup of 165 gigs was slow; 3 hours of rsync. But incremental backups of everything take just 5 minutes. 2.5 minutes of cp -al to make a historical snapshot and 2.5 minutes of rsync to update the primary backup. The incrementals are about 250 megs. Most of that are a couple of giant logfiles that get appended to on every email; rsnapshot has to back up the whole file.