This time last year, my primary hard disk decided to fail. As in, not just your typical "crash," but it physically just wouldn’t initialize at all. I’d never had that sort of failure before, and I hadn’t archived my data in a long time, so I ended up losing everything that had been on that HD. What I miss most is the irreplaceable e-mails from friends and family, for their sentimental value. I mean, not the typical short messages like "Are we meeting at 7?" but the true letters. Correspondence that cheered me up immensely.

But losing my primary disk and having to rebuild wasn’t a thrill either. So, just remember to back up your data on something pretty reliable (I would not recommend Zip disks or other removeable disks of that ilk) and make more than one copy, for safekeeping at different locations. If you don’t archive that often (every day/week/month), then at least do it every time you modify or add an important project or document. It’s cheap insurance.