I was rejected for Bizspark. As part of a wider product, I develop an Open Source OpenXML module for Python.

This requires testing on Office 2007 and 2010, as these apps don't implement the OpenXML spec exactly so there are quirks.

Not sure if the rejection was because it was whether the component that touched the MS stack was OSS, whether MS don't realize that Python runs on Windows, whether they don't want people to use OpenXML on other platforms, or some other reason.

Weirdly enough, I actually started in IT as a Windows NT 4 MCSE when I was 17. I had a very different view of Microsoft then.