[Jason Whittington] I’ve thought before about what it would be like to build a bootable managed platform. Rather than having the whole CLR run in user mode make the EE be the OS. Unmanaged code would be like “Kernel mode” and managed code would be like “User Mode”.

I’ve been wondering more and more about this lately. Even though Microsoft is moving forward with newer versions of Windows CE.NET and adding on the Compact Framework for managed applications, a componentized embedded operating system entirely built on an optimized CLR (such as the TinyCLR Jason mentions) would be extremely interesting.

Think about Longhorn for a second: “After that, there’s a version planned for Longhorn, which in many ways will be as revolutionary as the .NET Framework itself was - managed interfaces will eventually be the core of the operating system itself, not just a feature.“. Now scale it down for PDA’s.

Additional Reading: Laura OS, an operating system in C#, as well as Scott Hanselman’s Tiny Abstract OS.