A density oscillator: wax that floats when warm and sinks when cool, shaped as genuine metaballs so blobs neck, merge and relax back to round the way surface tension really makes them, lit only from the bulb at the base.
Drawn with: a WebGL2 shader.
Reacts to and looks like: gpu, webgl2 and audio-reactive.
Family: Visualiser.
Runs in your browser. The preview above is the same program the renderer uses.