Need to test your website against new and old versions of Microsoft Internet Explorer? Microsoft offers a set of VPCs free specifically for this purposes. They are downloadable as .vhd images, and include the base operating system. Of course.

http://www.microsoft.com/downloads/details.aspx?FamilyId=21EABB90-958F-4B64-B5F1-73D0A413C8EF&displaylang=en#filelist

These VPC images expire in April, 2009