For me it's an OS deployment technology. Creating bootable VHD's of full sysprep'd Windows OS's, then modifying the Windows bootloader to boot off the newly deployed VHD file the next time the system restarts. Manually having to install on each machine I want to deploy to right now since there is no truly portable/command line driven install yet for Windows. This allows me to deploy an OS to a machine behind the scenes so students can still be working with the current OS. But in a "multicast" type fashion so as to not bog down the fileserver completely.