I know it all too well. About a year ago, I accidentally downloaded something that brought massive amounts of spyware to my computer. Though I tried for weeks to clean it up and get rid of the annoyances, it became clear that nothing short of re-formatting the hard drive would get rid of the pests. I dutifully backed up everything I thought to be important to CD, then started the frightening task of a clean start. Only one problem. Somehow a directory or two missed getting backed up. A folder of minutes from my church meetings was annoying, but probably re-creatable. The Quicken file however, was costly and time-consuming to re-create (and had to be done before I could file taxes).
Since then, I’ve purchased an external hard drive where I dutifully back up all those important files and folders just in case something happens in the future. Plus, it’s been great to take infrequently used files off my hard drive and store them on my backup drive. Once the first full backup is complete, incremental backups take only a few minutes of my week while providing a great peace of mind.