You turn on your trusty old Linux box, and things are going well as you pass through the book loader, until the disk check reveals that your hard drive partition table is corrupt, and you are unable to access your machine. You need a good rescue disk -- and the best way to get one is to create your own.
You can customize an Ubuntu 8.04 Hardy Heron live CD to make a good bootable utilities disk by adding and removing packages from the standard installation. Specifically, you can remove most of the Ubuntu applications and install antivirus, a partition recover tool, a few disk utilities, and a rootkit checker, among other things. I'm going to create the live CD within an Ubuntu installation, but the directions should work for most Debian-based operating systems, and can be easily ported elsewhere.