This is a video of a Chladni plate experiment in which sand resonates to different frequencies to reveal a particular frequency& SECRET PATTERN. And we all love secret patterns here, right? Think of it as a special door knock.
Painting with sound, awesome! The artist Martin Klimas splattered paint in different colors over the diaphragm of a speaker. Then turning the volume up, the vibration of the speaker sent the paint aloft in patterns.