Sandboxes & Simulators

Drop an asteroid of your chosen size on any address and read back the fireball, wind speed and earthquake radius it makes.

Design a creature from joints and muscles, then watch a genetic algorithm spend hundreds of generations teaching it to limp.

Build a machine from wheels and rods to push a ball into a zone, and accept that it will topple over the first nine times.

Conway's cellular automaton with a library of known patterns, still the clearest demonstration that rules alone make worlds.

A free flight simulator in the browser using satellite terrain for the entire planet, with real air traffic overhead.

Combine two things to make a third, forever, until you have coaxed a language model into inventing something absurd.

Start with four elements and work towards seven hundred, most of which are jokes you only understand on arrival.

A cabinet of small physics experiments — cloth, water, ragdolls, particles — built by one developer who simply kept going.

A sealed glass sphere of water, sand and brine shrimp that you seed and then leave running, ecosystem permitting.

The sequel, with proper solid objects and adjustable gravity, and a public save gallery going back well over a decade.

A falling-sand game with several hundred materials that all react properly, including a dozen ways to end the world by mistake.

A playable account of why cooperation appears and then collapses, using game theory and roughly ten minutes of attention.

Click to place a block and a small algorithm builds a plausible seaside town around it, with no goal of any kind.