When developing for sharepoint (and other stuff) you may find it annoying to spend days setting up development environments, before you can start a single line of code. After a while your system gets filled up with all kinds of files og assemblies making it harder and harder to find errors and debugging. I find virtual development environments to be a way to save time and you can practically have a whole MOSS setup running on a single laptop. This guide gives you a head start of making a complete virtual MOSS environment for you to get started.
I used it to make a really cool virtual development image (although using VMware instead of VirtualPC) and have used it as base image for a lot of projects.
Good luck and enjoy 🙂