The latest version of Team Deploy (0.7.0.2) now contains the Device Controller Task. This task allows your Team Foundation Server builds to call the x10 Firecracker to control lamps. http://www.x10.com/automation/firecracker.htm
See the Team Deploy website on CodePlex for all of the details and files.
http://www.codeplex.com/TeamDeploy

Here's the street light we are using for our builds.
Build Smart Not Hard
Mike