"vvvv is a hybrid graphical/textual programming environment for easy prototyping and development. It is designed to facilitate the handling of large media environments with physical interfaces, real-time motion graphics, audio and video that can interact with many users simultaneously. vvvv is a hybrid graphical/textual programming environment for easy prototyping and development. It is designed to facilitate the handling of large media environments with physical interfaces, real-time motion graphics, audio and video that can interact with many users simultaneously. Responsible for its development is the vvvv group. vvvv is free for non-commercial use, commercial use requires a license."

Read more at http://vvvv.org/