Microsoft Singularity

At the annual Microsoft TechFest event—which began today at the company's headquarters in Redmond—Microsoft's senior vice president of research, Rich Rashid, announced that the source code of the Singularity project will be available for download from Microsoft's Codeplex web site.

Singularity is a Microsoft Research project started in 2003 to build a highly-dependable operating system in which the kernel, device drivers, and applications are all written in managed code. The lowest-level x86 interrupt dispatch code is written in assembly language and C. Once this code has done its job, it calls the kernel, whose runtime and garbage collector are written in C# and run in unsafe mode. The hardware abstraction layer is written in C++ and runs in safe mode.
The Singularity project illuminates the broader implications of using managed code to develop operating system components. Although we probably won't see anything like Singularity running on desktop computers any time in the near future, the concepts have a lot of theoretical merit and will likely interest many in the academic community.