Every now and then, a computer moment arrives which sends a shock through your system, as you are reminded that these devices aren't immortal, and that ignoring data backups is like trusting the chamber to be empty when you put a gun to your head. For the first time, my RAID array rebuilt itself tonight. I have no idea what caused the rebuild, but suddenly, I'm more happy than ever that there are mirrored drives humming away in my case. If I only had a single drive, I have no idea what shape I'd be in right now. Three cheers for redundancy!