Yes, that was our main reason for joining BizSpark, to be honest. We're a "pure play open source" company and absolutely favor running on OSS / Free Software platforms, and we encourage people to fun our products on Linux, a BSD UNIX, etc. But, in real-life, Windows, Office, Exchange, Sharepoint, etc. are out there, close to ubiquitous, and sometimes you have to work with that stuff. So BizSpark is a great way to get your hands on all of the MS "stuff" for testing, integration, etc.