Since my presentation on KulenDayz 2009 is over, I will share here PowerShell scripts for creating and mounting virtual disks under Windows Server 2008 R2. For those who really need it on Windows 7, there is solution with C# dll called from PowerShell (or just use small sample application).
Here are also links to some older post that cover most of what I was speaking about:
If you are C# soul, you may also want to check my WinDays post.