While researching for the previous post, I just started a few searches for VSHADOW on the internet, and I found more interesting usages of it. One example: EqualLogic published a nice technical report of using VSHADOW to backup/restore Exchange, SQL and NTFS. Here is the link:
Just to bring you up to speed: VSHADOW was written to showcase for VSS backup and restore capabilities. The source code is available on the VSS SDK. You can use VSHADOW to backup/restore Exchange/SQL/NTFS on any hardware array that implements VSS HW providers, in a similar way as outlined in the paper above.
P.S. BTW - standard disclaimers apply. I am not affiliated in any way with EqualLogic.