In my current project my coworker Christoph an I decided to build our own eXtreme feedback device for our continious build. We started with the NET-PwrCtrl HOME a power outlet controlled over ethernet.
We came out with the idea to project the batman sign on our office ceiling. That was pretty straight forward. Christoph bought a bright led spot and cut out the batman sign of paperboard. Fixed it with some wire on the lamp and ready was our office batman projection.
We control the power outlet with a small Java program Christoph has written. The software PowerControl is available github. The PowerControl.jar is called from an ant target in our project cruisecontrol server when our build fails, and we have a fancy batman sign on our office ceiling that remembers us to fix the build.