Many people think that Microsoft and OS movement have nothing in common. Well, they are wrong. Just take a look at Open Source at Microsoft web site. Brad Wilson provides more personal experience with Open Source at Microsoft in his interview. Recommended reading.

There is a bunch of Iron* CLR-based language implementations that are provided by Microsoft to the Community as open source projects. Take for example IronPython, my favourite among them. I know that many of you will actually prefer IronRuby. It his there too.

If you haven't seen CodePlex yet I recommend that you do. CodePlex is a website for programmers that would like to publish their open source projects that relate to Microsoft technologies. One of my favourite projects there is Script# - it will be your favourite too if you know C# and JavaScript is rather a mystery for you. Script# allows you to write Ajax applications in C# that is later on "compiled" to JavaScript. Cool.

You may find a lot of interesting blogs that relate to Open Source topics on Port25. Recent hot topic: parallel programming.