Today my 1TB Seagate 7200rpm Barracuda hard drive crashed. It was a hardware failure. If you can detect the disc in the BIOS, you can use some or the other software to recover the data. If it does not get detected in the BIOS, there are options, but costly ones. The best part is, now Ubuntu 9.10 has a built-in utility to warn you against disc failure – Palimpsest. I ignored the warning 
I lost close to 970GB worth of data. Many of my favourite documentaries, teaching company video courses, television series and TED videos are gone.
I was shattered. But not to the extent of getting depressed. I lost a camera worth 1.5lakhs on the road, last year. I am used to such losses now 
But there was something else that really made me ignore my loss. This morning I was at St. John’s donating blood for my mother friends who has been diagnosed with blood cancer. When I met the family, I could see the loss they were anticipating in their eyes. I know that I always buy my camera back one day, download all the data on the internet and fill my hard disk again. But losing a family member is just huge. Certain things can never come back.
I have had similar bad experiences with hard drives. RAID is the way to go.