Microsoft "White Hat Hackers" Blog
Are you a security junkie? Then you should keep a watch on Microsoft's White Hat Hackers Blog:
"We employ "white hat hackers" who spend their time pentesting and code reviewing applications and software looking for weaknesses and vulnerabilities so that others don't once we've released that code into the wild. We employ many many smart testers who know more about some of our software then perhaps the architects who designed it. We also employ some of the top researchers in their industry, dedicated people working on the bleeding edge of whats going to be common place in the next 5 or 10 years of computing. So yes, Microsoft does have hackers, and its time to introduce you to some of them and show you what it is, exactly that they do."
Check out http://blogs.msdn.com/hackers