Play a Theremin with Your Bare Hands in the Browser
Air Theremin – a browser theremin you play by waving at your webcam

Air Theremin turns your webcam into a musical instrument: wave both hands to control volume and pitch, lean back to soften the tone, and bring palms together for silence. On phones, tilt the device instead—left-right for volume, forward-back for pitch. No camera or gyro? Use the mouse. Created by Pavel Gurov, based on theremin.site.
SPREAD HANDS = LOUDER · PALMS TOGETHER = SILENCE