Note: this post is from 2007, outbound links may be broken.
Microsoft Internet Explorer Application Compatibility VPC Image (free)
Screenshot of Microsoft Virtual PC 2007
The images should come in handy for anyone running Windows Vista who wants to see how their web page look in Internet Explorer under Windows XP. Of course, you could also run the disc image inside of Virtual PC if you want to try installing new software without risking any damage to your host operating system.
Both disc images will expire on August 17th, 2007. The images are pre-activated so no hassle running them (Windows only). Download the disc images here.