I did not...
A while back my Western Digital 500GB MyBook had a breakdown during the transfer of a batch of large files. This had happened to me a coupe of times before where Windows would display a Delay Write Failed error message, and some times it would have problems detecting the disk. Running scandisk and/or rebooting always seemed to fix the problem, so I didn't give it much attention, but this time it was different. The disk could no longer be detected by Windows, SpinRite or Western Digital's own maintenance tools. I tried the disk in several different computers with the same result.
When the system tried to boot the disk it would spin up and emit a series of rather loud clicking sounds before spinning down again. Many hours of googling led me to the conclusion that the disk had in fact suffered mechanical failure, and that I should have picked up the previous Delay Write Failed errors as a warning that the disk was about to fail. As it is now, the only option I have to recover the data is to have it sent to a data recovery specialist where they remove the data plates from the faulty drive housing and place them in a new one. This has to be done in a Class 100 Clean Room because even a microscopic spec of dust could lead to permanent loss of data when the disk is powered up again. Needless to say this service is not cheap.
This disk contained all my original RAW files from the last 2-3 years, and since I had never bothered to burn a backup DVD, these pictures are now most likely lost forever! The disk sits in my bookshelf as a grim reminder of my own stupidity awaiting the day I decide to fork out the big bucks and send it off for recovery. So the moral of the story is, always backup your files!