Anyone like me who uses a computer to make their daily living and yet who doesn't back it up regularly is being a fool. Seriously, it's one of the most stupid things you can do: use a temperamental, buggy, likely to fall over machine and not make sure that your data is safely stored.
There are so many stories of manuscripts for novels residing on defunct hard drives, reports that had to be in yesterday that are fried by a motherboard going up, or a power surge.
There are a number of ways of dealing with this but the one that seems simplest to me is IBackup - Online Backup and Storage. Yes, you can play around with software and back up your files manually, yes, you can play interesting games with Gmail and other things, but really, who has time to do all of those things?
Why not simply pay the minimal sum necessary to have all of this done for you automatically? Get signed up to the IBackup - Online Backup and Storage system and it's all done automatically for you overnight while you're asleep but your broadband connection is still on.
There are other benefits too: instead of having to search for your files amongst your backup media you can review them remotely from any computer via a simple browser or as a mapped drive on your own computer.
Yes, there are free services out there but really. For this cost it's not even worth taking the time to go and search for them. It just seems such a simple decision to me, making sure that all of your work is safe and sound, both backed up properly and also stored offsite.