I can't believe nobody has posted this on here yet today! Microsoft released 20,000 lines of source code to the Linux kernel - released under the GPL. Microsoft is going to maintain said code in the kernel.
I am not making this up. http://www.networkworld.com/news/2009/072009-microsoft-linux-source-code.html http://blogs.zdnet.com/microsoft/?p=3403 (Or search on news.google.com for the word "microsoft" today)
