Emberflux
Tilt a warm molten surface and conduct where it boils — a real Rayleigh–Bénard convection layer that self-organizes into overturning cells, reorganizes over time, and sings its own overturning.
Heat rises from the bottom in bright plumes; cool fluid sinks in dark lanes; the layer settles into a honeycomb of cells and keeps reorganizing. Tilt your phone to lean gravity and drift the boil. No tilt sensor? A seeded auto-conductor drives it for you.
Best with headphones. A low convective drone, inharmonic overturn chimes — slow glow, no flashing.