At risk of descending into the traditional backup rant, it's not just if the hard drive goes. Many of us use laptops, which are (as I know only too well, see below) a magnet for scumbags, ne-er do wells, and thieves of all sorts.

Irritatingly, so are CDs, so don't store your only data backups on the CD rack next to the collected works of Britney! For my part, I keep a 'core' of absolutely vital stuff in a particular directory, ruthlessly keep it below 256MB, and back it up onto a pen drive on my keyring 1ce a week, as well as other backups. When working on something important I periodically email it to an offsite location (home if at work, work if at home).

Two weeks ago that habit saved me from disaster. My laptop was stolen at the end of a weeks holiday, taken specifically to work on my dissertation. 4 days later I had replaced it and retrieved the copy of the document I had mailed to work - without a single word lost.