Microsoft has put a fair amount of marketing muscle into their Unified Communications offering. Many organizations are busy architecting, deploying, and implementing the various components- Exchange Server 2007, Office Communications Server 2007, the OCS 2007 Mediation Server, etc. The standard, supported configuration involves separate server hardware for most of the components, and an on-site PBX solution. Evangelyze Communications however, working with VoIP provider NGT (New Global Telecom) has built a fully functional Microsoft Unified Communications deployment running almost entirely virtualized in Hyper-V, and connected remotely to a hosted VoIP service. You can learn more from Mike Stacy’s blog: Hosted Gateway/SIP Trunk with OCS. The result is a Microsoft Unified Communications deployment with significant cost savings in terms of hardware and infrastructure.