Fun

Some fun, sometimes interactive, things built either for interest or to help understand them better.

Machine learning & AI

Add a sliver of carefully aimed noise to a digit and watch a neural network change its answer, while the image looks unchanged.

A reinforcement-learning agent lands a rocket. Change gravity, wind, or the pad and watch it cope.

Fling masses into orbit and watch Newtonian gravity pull them together, merge, and trace long paths.

Drop bar magnets and watch their field lines weave; opposite poles snap together, like poles repel.

Two pendulums start a hair apart and end up with nothing in common. Chaos, on screen.

A full-screen cellular automaton you can draw on. Change the rules or drop in classic patterns.

Every cell is a person. Start an outbreak, tune how it spreads, then vaccinate and watch herd immunity.

Watch SHA-256's avalanche effect, then find a real CRC32 collision in a fraction of a second.

Why a bond's price falls when rates rise. Drag the rate and watch today's price move.

How each payment splits between interest and principal, and why paying extra early saves a lot.

Why holding many investments narrows outcomes while keeping the upside, and how fees skim the top.

Resize an image to a target file size, crop, rotate, strip EXIF, or make a favicon pack. All in your browser.

Merge, split, reorder, rotate, redact, sign, and fill PDFs. Private and in-browser; nothing is uploaded.