For the MAX workshop Nils Rotgans and I wanted to make a Chladni plate. It's basically a metal plate mounted onto a speaker. As an input for the plate we used a EEG reader toy that reads your brainwaves. We read the values of the EEG reader with Processing and ported it to MAX which generates sine waves of it. When the plate vibrate at a certain frequency pattern can be seen when sprinkling salt, sugar or silicagel. The idea was that every state of mind had its own pattern.