I've written before about Mozy, an automatic backup utility. It's a nice way to backup your files in another location so that if something happens to your computer, you can get them back.
Mozy has just announced a version for the Mac. You can download the software and automatically back up your data.
The main drawback is that, unlike Mozy for the PC, the Mac version is not free. You will need to buy a subscription for $4.95 a month. Still, it may be worth it to keep your data safe, both from a computer crash, and when you get a new computer and want to transfer files.