I was searching around in the US Patent Office database this evening to find my patent for consistency checking of a backup without restoring the backup, for a Twitter conversation I was having, when I discovered that another one I filed before leaving Microsoft was granted in late 2009.
The new one was part of the old WinFS system – it deals with doing consistency checks on partial user-defined complex data structures as they're being read from a streaming data source so that inconsistencies can be discovered as soon as possible. Unlike the backup one, I actually wrote the code to implement this one (although it never shipped when WinFS was canned).
You can read about the patent (if you have insomnia) here.
I always wondered if that patent was dropped on the floor – now I know I've got two software patents :-)