Norton Ghost is your friend. As others have suggested, get another drive, and clone it. It's probably cheaper than a tape drive and definitely faster. A Ghosted drive is fully bootable and runs the same as your original so, when your drive dies, you just pop in the backup, you keep stepping with the backup, and all you're out is the cost of a new backup drive. Once you're done with your original task, you can keep Ghosting as often as you wish. I can clone my 20 GB drive in 10 minutes.
The really cool way to do it is to buy a Mobile Rack, a device that mounts in a 5 1/4" bay and accepts a slide in trey that holds your clone drive. Ghost is run from a bootable floppy, so all you have to do is plug in the drive, boot up, clone the drive, and remove it to a safe place until the next time.