The Brain Opera is an attempt to bring expression and creativity to everyone, in public or at home, by combining an exceptionally large number of interactive modes into a single, coherent experience. The project connects a series of hyperinstruments designed for the general public with a performance and a series of real-time music activities on the Internet. Audiences explore the hands-on instruments (i.e., Harmonic Driving, Melody Easel, Gesture Wall, Rhythm Tree, Speaking and Signing Trees, etc.) as preparation for the performance, creating personal music that makes each performance unique. The Brain Opera attempts to redefine the nature of collective interaction in public places, as well as to explore the possibilities of expressive objects and environments for the workplace and home. Since its 1996 premiere and world tour through 1998 (United States, Europe, Asia, and South America), much has been learned about interactive software and interfaces, Internet music systems, and intelligent, evolving environments for creativity and expression. We are currently incorporating these new ideas, and designing significant upgrades and new features for the final version of the Brain Opera, which was permanently installed at the new House of Music in Vienna, Austria in July 2000.