Zero and Random device driver

http://www.acc.umu.se/~bosse. Windows driver examples with free source code related to file systems, virtual disks and network communication from kernel mode (HttpDisk, …).

http://stackoverflow.com/questions/1325568/easiest-way-to-program-a-virtual-file-system-in-windows-with-python

http://www.eldos.com/cbfs/

http://www.codeproject.com/KB/dotnet/DataObjectEx.aspx

I would look at a container file format. VHD is well documented along with HDI and (embedded) OSQ.