For some time now, VMware has been pushing the concept of virtual appliances as a new method of software distribution – a pre-built, pre-configured and ready-to-run software application packaged with the operating system inside a virtual machine – and the company has many pre-configured VMware virtual machines ready for download. Now Microsoft has come onboard, encouraging users to download pre-configured .VHD virtual hard disk images for Virtual PC or Virtual Server.

Microsoft sees this as an opportunity for customers to quickly evaluate Microsoft and partner solutions for free in their own environment without the need for dedicated servers or complex installations. VMware’s vision is a little broader and their Virtual Appliance Marketplace holds links to hundreds of virtual appliances from software companies as well as the open source community.

It’s certainly an interesting concept. Instead of installing an application on an operating system and then configuring it to suit, I can take an existing image, pre-configured by the software developers according to their best practice and greatly reduce the time to deploy an application. Of course, there will be issues around standard operating system configurations (many organisations will not accept an application unless it runs on their hardened operating system build) but this use of virtualisation technology has huge potential – and not just for demoware.