Other recent efforts include its Windows Azure OS, a cloud computing OS currently offered for free to developers.

Now Microsoft has unveiled another new OS prototype codenamed "Barrelfish".  Barrelfish is an OS optimized to run on multi-core machines.  Namely, Barrelfish uses message passing and a database like system to pass information between cores.  Typically OS's use share memory schemes, which become very inefficient when resource demands are high.

The new OS was jointly created by ETH Zurich, a technology university, and Microsoft Research, located in Cambridge, Mass. 

Interestingly, it uses some open source BSD third-part libraries, which are "covered by various BSD-like open source licenses."  This has led to speculation that the new OS may be free and open source, not terms you typically would associate with Microsoft.

According to developers who have attended conferences on the new OS, it reportedly brings some of the Midori/Singularity sandboxing protections onboard.  Additionally, applications reportedly have an alternate route of accessing information from devices like graphics or sound cards.  A large deal of device information is reportedly stored in a central database that can be queried.

Writes developer "AudriUSA", "... instead of fully isolating program from device via driver, Barrelfish has a kind of database where lots of low level information about the hardware can be found. The kernel is single threaded and non preemptive. Scheduling is coupled with the message passing, an arrival of the message simply activates the waiting thread. It also uses a little bit of the microkernel concepts, running drivers in protected space, like L4 and in general pushing a lot into application domains."

As Intel and AMD expand their 4, 6, and 8-core lineups and approach even higher core counts, using these resources efficiently will be a crucial operating system responsibility.  It will be exciting to see what kind of improvements that Microsoft can accomplish with Barrelfish, as these improvements will surely be rolled into successors to Windows 7.