Play,
combine,
discover.

Chain Reaction — One-Click Particle Puzzle

Choose one moment and one position, then watch a single explosion spread through a field of moving particles.

Cosmic Simulator — Build and Evolve a Universe

Trigger a Big Bang and watch matter form stars, planets, neutron stars, pulsars, quasars, and black holes.

Magnet Factory — Physics Puzzle Game

Guide a metallic ball through physics puzzles, or build your own route with permanent attraction and repulsion magnets.

Falling Sand 3 — Heat and Material Sandbox

Explore heat and material reactions in Falling Sand 3. Melt ice and wax, mix lava with water, and build experiments with continuous generators.

Ripples — Wave Interference Simulator

Explore wave interference with two sources in a free ripple tank simulator. Adjust frequency and amplitude, compare borders, and save your setup.

One Man Band — Free Online Music Loop Maker

Build a browser beat with a 16-step sequencer, drums, bass, keys and horn. Change tempo and swing live, then share your rhythm.

Falling Sand Game — Play Free Online

Play the classic falling sand game online. Draw sand, water, oil and fire, build walls, and save your sandbox creations. No download or sign-up.

Falling Sand 2 — Lava and Acid Sandbox

Experiment with lava, acid, water and sand in Falling Sand 2. Paint particle scenes, save a snapshot, or download your creation to continue later.

BioSim — Artificial Life and Ecosystem Simulator

Explore an artificial ecosystem with herbivores, carnivores and hybrids. Change food supply, observe populations, and inspect individual agents.

Artificial ecosystem experiment: change the food supply

Use BioSim to compare food supply settings and observe herbivores, carnivores and hybrids. Record what changes without assuming a fixed outcome.

Falling Sand experiment: ice, heat and lava

Build a small material experiment in Falling Sand 3. Compare ice with and without nearby heat, then observe what happens when lava meets water.

Wave interference: an experiment with two sources

Compare one wave source with two in Ripples. Change their spacing, observe interference patterns, and save a setup for your next comparison.

Geek curiosities

Moving sand art: a different landscape with every turn

Sand, liquid and bubbles build mountains inside a frame. Discover what to watch in moving sand art and what to compare before choosing one.

Science activities

Turing Tumble: can a marble follow a program?

Build logic with parts and marbles. Explore Turing Tumble: predictions, mechanical memory and the satisfaction of finding a flaw in your design.

Brain teasers

Rush Hour: when moving backward is the only way out

A red car, an exit and a gridlock of obstacles. Explore Rush Hour through planning: predict moves, trace dependencies and escape the jam.