Hold the mouse button and drag. Luminous fluid follows your cursor, curls into vortices, blends where colours meet, and slowly settles. A control panel in the corner lets you change quality, colour and dissipation.

It earns its place on a site about a liquid-sorting puzzle for the obvious reason: it is the same material Magic Sort is made of, with the rules taken away. Where the puzzle asks you to separate colours, this lets you mix them.

Turn the dissipation down and the trails persist long enough to draw with. Turn it up and everything fades almost immediately, which is the more meditative setting.

No goal, no end, no score. A screensaver you can push around.