Backup your Mac online with Mozy
There's a dearth of companies offering backup solutions for Mac users. While some may say that's because Macs don't crash as frequently as Windows machines, that doesn't help if you happen to have your Macbook stolen.
Mozy lets you store up to 2GB of data online for free, and charges $5/month for unlimited storage. You can either backup your entire hard drive on a regular basis, or you can do a partial backup covering specific files like your iTunes or iPhoto collections.
You'll need Mac OS X 10.4 to play with the new beta.