For the last few years, I'd forced myself to make weekly backups to CD-ROM. Then, when I outgrew 650MB of backup space, I switched to DVD-R. That worked, but backing up was goddawful slow - bringing my system to it's knees during the backup process. Eventually, I got lax about backing up. It's been months since I've burned a backup disk, and I was starting to get a little nervous. I had been using a tiny portable hard drive, but it was small enough that I had to skip entire directories.
But, today Kevin The IT Elf dropped by my cube with a box - a LaCie Big Disk Extreme - 500GB (half a freaking terabyte) of room to backup with. And I think it comes with every modern connection type - Firewire 400, Firewire 800, and USB 2.0.
LaCie also provides a decent backup app in SilverKeeper - which will automatically backup stuff like my entire ~/dnorman directory, without making my system unusable during backup.
So, now I'll set my Powerbook to backup via rsynch to my desktop, which will backup to the BDE automatically every morning at 2am. And hope an EMP doesn't clear all of the platters...
I'm going to sound old here, but I used to have a top-of-the-line FWB RAID system for doing video in the mid-ninetees. 18GB, divided into 10 partitions. On a good day, it could push 5 megs per second. And it cost around $20K. Now, I get 25X the capacity, an order of magnitude increase in performance, for about $400. Heck, my iPod has more room and outperforms that early RAID. I'm a little scared about what kind of storage will be available in another 10 years...
Update: Don't forget to disable Spotlight on big backup drives...