When I was 15, I once came back from a LAN party only for my HD to turn to slag that day. Lost years worth of music, pictures, project files, utility software, and various configurations.
Several years later, it nearly
happened again with another computer. It was starting to get old and what happened was just a boot error. I was angry, and then I got over it, and about an hour later everything seemed to work again. I backed everything up and started looking for a new computer.
On my most recent RM project, I had a similar configuration error (as mentioned in above post) cause me to lose a couple hours worth of work. Not because I couldn't get around the configuration problem (made a new project, copied things over), but as a result of a few seconds of panic that caused me to *not* copy over some files into the right folder. A couple files were overwritten with blanks ... and that was all it took.
Generally speaking, I back up what I can and try to be at peace with starting over when catastrophe strikes. I have lost and been forced to start over many, many projects in my time, and it's only been in the last few years that I've started to find new uses for old project data, so I can move forward with things it turned out weren't quite all-dead.
It's a rough life when you're a creative-type.