Microsoft has released not one but several pieces of code as open source. Moreover, it's submitting some of its home-grown licences to the Open Source Initiative for approval. So what is going on here? In part, I think that Microsoft's own analysis of its motives is true: we do live in a heterogeneous world of technology, and the creation of Microsoft's open source pages and projects reflects a long-overdue reflection of this fact. It is also testimony to the continuing success of free software.