The contributors over at Channel 8, the web community for students interested in computer technology, are really turning us some interesting things. Recently there was a student interview with Bill Gates and then the other day I read about Cosmos. Cosmos is an operating system that is being written in C#. It's an open source project so you can get the code and mess with it yourself. Yeah, I know, you can do that with Linux too. Of course you have to be pretty good in C/C++ to mess with Linux and Linux has grown to be a pretty large bit of code these days. Sometimes one wants to dig into something a little more manageable.
Cosmos is still pretty small and there appear to be a lot of pieces that are either waiting for someone to implement or not quite so far done that there is nothing left for others to do. At the Channel 8 article you will find some step by step instructions for getting it up and running in a Virtual PC environment. And of course links to the code.
As for me, I'm wondering how I can find some time to play with some shell ideas I have running through my head.
Microsoft Research has released the Singularity Research Development Kit (RDK) and it is now available