Interactive ceiling design and realization in a hall of a protestant church. Here people meet before and after the service, and often engage in informal talks, while their children are running around. Because it is often very busy place close attention was paid to the lighting and acoustic conditions. Custom made LED lights are wired individually and in the next stage can be connected to a microprocessor. That would enable to switch between different lighting modes including the "game mode" that would be used by youth groups gathering in the adjacent rooms.