Ok, this isn't actually security related but its interesting nevertheless: A nifty third-party tool cracks some Windows 7 files to reveal hidden features previously only available to Microsoft employees.
The tool, Blue Badge, was developed by Rafael Rivera. When run it will modify 10 executables and DLLs to remove domain and username restrictions. With that done Windows 7 will then allow you access to additional features such as gestures, panning, and the Desktop Slideshow.
Rivera has made Blue Badge available for x86 platforms and plans to release an x64 version sometime soon.
If you plan on trying the tool then be sure to read the comments on Rivera's blog to learn about potential problems that you might encounter.
What I find interesting about this crack is that it apparently works without causing Windows 7 to detect that it has taken place. That is to say Windows 7 will run and won't complain about the modified files.