Microsoft opens source code for Windows CE 6
Microsoft released kernel's source code for its Windows CE 6.
The source code is licensed under Shared Source license, which is similar to BSD license but prohibits use of the code for commercial purposes.
The fact that the kernel is available for hacking may actually lead to the development of open source software or even a variant of operating system using Windows CE 6 kernel.
You can read a detailed report here: Windows CE 6 arrives with 100% kernel source