I couldn't agree more with this. You could also look into VirtualBox as a virtualization solution. You might not want to choose this route if you want to use X

I couldn't agree more with this. You could also look into VirtualBox as a virtualization solution. You might not want to choose this route if you want to use X windows because personally, switching back and forth between desktops is just plain annoying (and last I checked, Seamless mode only works with Windows). Also, if you're going to be testing hardware on linux, you'll probably be better off getting a new machine. But for all other cases, virtualization is the way to go. My current setup is a Macbook with an Ubuntu 7.10 server VM for development (nothing beats apt).