Signifying how important the virtualization market is, Microsoft has started to give away it's virtual server product. If you are a developer and you've never seen how virtual server and virtual machines like Microsoft VPC or VMWare's VM can make your life easier, then you haven't lived yet. Imagine the ability to build a development or test machine, then totally screw it up, then undo everything and go back to where you were when everything worked? What about working on several products at the same time - perhaps mutually exclusive versions of the same product? The possibilities are limitless because a virtual machine is, in almost every respect, a real machine. It runs with it's own memory, it's own hard drive, and it's own COM ports. These virtual machines are also far more portable than a real machine - you can FTP them or trade them with your friends on DVDs.