One open source project I have been keeping an eye on is CoApp. Microsoft is currently paying a Garrett Serack to develop an open binary and source package management platform for Windows. The goal is provide the ease of use and flexibility of linux-style package management on the Windows platform. This is exactly what Microsoft needs to do to keep its operating system competitive in the current climate. Anyone that has developed or broadly deployed an open source application on windows knows the pain that can be avoided if this project succeeds.