I've had two major hard drive crashes that are fairly traumatic. The first was over a decade ago, when my computer refused to boot because the hard drive wouldn't start up... that was when someone taught me the "banging" trick and I was able to save the hard drive long enough to keep it running.
The second time, I dropped an external hard drive and had no such luck... the drive was long gone and wouldn't turn on again... 500 gigs of data lost! At least Seagate was good about replacing it for me.