Soma has a post today on our self-hosting of Team System, which we often refer to as "dogfooding".
The team that is building the lifecycle tools is about 300+ strong and is spread across 3 different locations geographically. This team has now been self-hosting on what they are building for their day to day development activities for more than 12 months now. This means that the source code that they have for these tools are now stored in their source control repository. This means they are using the issue tracking system for tracking issues in the project. This means they are using MS Build for building the tools. This means they are using reporting capabilities to get insight into the status of the project.