Ten minutes to kill

The forecast as an animated map, with wind, waves, temperature and a dozen models to argue between, free and without an account.

Answers computed rather than retrieved: integrals, unit conversions, orbital mechanics and the nutritional content of a Mars bar.

Six goes at one five-letter word, the same word for everybody, once a day. The puzzle that spawned an entire genre in three months.

Renders your text in every font installed on the machine at once, which is the fastest way ever devised to pick one.

A dictionary showing real usage, related words and examples pulled from the wild rather than agreed by committee.

Readings from thousands of air monitoring stations worldwide on one map, colour-coded from a calm green to a genuinely alarming maroon.

Guess the country from its silhouette alone, with each miss handing you the distance and compass bearing to the real answer.

Live counters for population, emissions, water use and books published, ticking faster than is entirely comfortable.

One expanding circle to breathe along with, adjustable to box breathing or 4-7-8, and nothing else on the page.

A vast, barely filtered pile of browser games including a great many Flash-era oddities kept alive by an emulator.

Widely reckoned the strongest reverse image search for faces, places and heavily cropped photos. Worth trying when TinEye finds nothing.

Unicode styling for places that forbid formatting, so bold and italic survive a paste into a profile bio.

Old Faithful on a live feed, plus static cameras on the geyser basin and the north entrance, run by the National Park Service.

The Norwegian met office's forecast, famously accurate across Scandinavia and unusually calm about admitting uncertainty everywhere else.

Piles combining diacritics onto every character until your text bleeds into the lines above and below it.

Two minutes of mental arithmetic at whatever difficulty you set, boiled down to a single number. Trading desks drill on this one.

You can do anything at Zombo.com. The welcome message has been loading since 1999 and it has never once explained itself.

Satellite imagery refreshed through the day, with storm tracks, wildfire hotspots and rainfall radar layered over the top of it.

Feeds your own video call bad audio — echo, crying baby, wind — until everyone agrees the connection is the problem.

The sequel quilt, darker and stranger than the first, still folding into itself with no end and no explanation.

A space shooter where you destroy incoming words by typing them, and rising panic is the entire difficulty curve.