@nixCraft
"Always backup the backup of your backup."
I once had my laptop die WHILE I was copying one backup to a 2nd #backup. 
"No problem!" I said, as I called all THREE of my long-distance brothers, to whom I had sent a copy of ALL my over-10,000 #Genealogy files (sorted & organized into lots of sub-sub-sub-directories).
Two had not kept any files, after browsing through the interesting family photos. 
The other one had kept the flash drive, so he mailed it back to me...
He had also deleted ALL the files.
"No problem," I said again. After all, I was married to a computer guy. Surely he could fix it...
Hubby ran a recovery program for 3 DAYS, but was only able to recover the photos and documents. ALL videos of interviews with dead relatives were unsalvagable.
To make matters worse, some files were still useless, I had many duplicates, and my directory structure was GONE
That was three YEARS ago. I'm still sorting the mess out.