Stopped by Fry's today to pickup a firewire drive setup to run backups of my Powerbook. I knew just what I needed because I had made a previous trip with nf0and saw the rig he went with.
I started with an Acommdata 3.5" USB/Firewire enclosure and married that to a 400GB Hitatchi HD. This turned out to be a great setup – not to mention a great deal compared to an off-the-shelf high capacity firewire drive.
I'm using SuperDuper for my user data backups. I tried a couple Mac OS X backup utilities, but SuperDuper is very simple to use and pretty fast. It allows you to make pain-free, reliable backups. I gladly paid the registration – it's great software. (Plus Dave has a SuperDuper blog, which makes it easy to get the skinny.) I understand that SuperDuper Version 2.0 is coming out soon, so I'll be upgrading.
For extra data security, I'll occasionally connect the USB to the Windows network and zip up my Mac backups onto the network server.
OK, I just re-read this post and it sounds way to geek-a-rific. I gotta get back to football!!