CodeParade proposes an very interesting game/game engine that uses a smart physics computation related to fractal rendering. The result is Marble Marcher, an opensource (GPL-2!) game, available on itch.io and github.
- download on itch.io (windows only): https://codeparade.itch.io/marblemarcher
- compile the source: https://github.com/HackerPoet/MarbleMarcher