Coffee break

Backgammon against ranked humans, with an analysis pass afterwards that quantifies precisely how reckless your doubles were.

Filter by genre, format and city to find records sold directly by the people who made them, with full streams before you buy anything.

Minimalist colour puzzle rooms — yellow, blue, red — where every level teaches you a rule the game never states out loud.

Chiptune tracker with a whole song's worth of channels, shareable as a URL that contains the entire tune inside it.

Photo editor and collage maker aimed squarely at people who want a decent result without learning anything first.

Annual contest in which vision scientists compete to fool you, with every finalist since 2005 still watchable.

Maths explained by intuition first and formulas second, by someone who clearly resented how he was taught it.

The personality model psychologists actually use, in a clean 120-question version with a proper breakdown of every facet.

Anonymous celebrity riddles where readers do the detective work in the comments and are occasionally proved right.

Community for adding glitter, sparkles and animated hearts to photographs, still busily active long after the trend died.

The volunteer lightning detection network behind most live strike maps, with raw data and instructions for building your own receiver.

Monkeys pop balloons along a fixed path, and the upgrade trees behind that sentence are deep enough to justify the reputation.

Browser Minecraft with party modes bolted on — parkour, bed wars, one-block survival — and multiplayer that joins in one click.

Roll a rectangular block across floating tiles into a hole, with switches placed to force you to think in three dimensions.

Several hundred properly licensed board games with the rules enforced for you, so nobody argues about whether that move was legal.

The original boredom portal, still sorting thousands of time-wasters into categories with no discernible editorial filter.

Plain, well-sorted illusion collection with the explanation directly underneath each one, from café walls to impossible triangles.

Dual n-back, the working-memory drill psychologists keep arguing about, implemented properly and charted over time.

A scrappy free collection of brain teasers and n-back drills that has been quietly online since long before the app stores existed.

A German board game world that has hosted Carcassonne and Puerto Rico since 2001, complete with a slightly baffling lobby.

The write-draw-write chain game that predates the current crop, still running, still free and still producing pure nonsense.

Brown bears standing in an Alaskan waterfall catching salmon in mid-air, live from Katmai, and the reason Fat Bear Week exists.

One page per leak channel — WebGL, canvas, WebRTC, DNS — each showing precisely what your browser hands over without being asked.

Every recipe costed per serving and per batch, with step photos throughout. Built for people cooking against an actual number.

Weaponised arcade racing around an open city, with the loud handling model of a mid-2000s console game.

Enormous plain-text library explaining what every placement and aspect is supposed to mean, unpaywalled since the early 2000s.

A collage assembled entirely from GeoCities pages — every GIF, marquee and tiled background salvaged and put back to work.

Two near-identical interfaces, one of them subtly wrong. Getting past the third level takes an unreasonable amount of care.

Thirty-odd card games with competent bots, no accounts and nothing covering the table. The default answer to fancying a game.

The four-day jam game that grew into Celeste: thirty screens of very precise dashing, running in the page at PICO-8 resolution.

Per-component checklists — buttons, forms, cards, empty states — covering the things everyone forgets until review.

A stocked chemistry bench in the browser where you can mix reagents and get it badly wrong at no cost.

Community-written choose-your-path stories with ratings, which is the only thing keeping the good ones above the fan fiction.

Google's stripped-back sketchpad — pencil, pen, marker, chalk — with pressure support and absolutely no other features.

Fourteen small experiments — spectrogram, harmonics, arpeggios — that explain how music works by letting you break it.

How far you can get by train from any European station in five hours, drawn as coloured bands. Ruinous for an afternoon's productivity.

Parody religion with its own prophet, apocalypse date and merchandise, committed to the bit long enough that you stop being sure.

Open-city driving with traffic and no mission attached, for when you want to obey a speed limit in peace.

Video walks through a real city, and your job is to work out which one from the shopfronts, number plates and pedestrians.

Decades of adverts preserved exactly as broadcast, including the jingles you will regret having remembered.

Several thousand DOS, Amiga and console titles catalogued with screenshots, each playable without leaving the page.

Viral-content parody taken well past the point of sense, including quizzes that insult you for finishing them.

A global membership devoted to looking up, with a cloud of the day and a manifesto against blue-sky thinking.

The word-association board game in a free, well-built online room: two spymasters, one grid of code names, nothing to install.

Run a coffee stand for fourteen days, adjusting recipe and price daily, and learn more about margins than from any lecture.

A plain, ad-free bank of cognitive tests — n-back, digit span, Stroop, mental rotation — that keeps a history of your scores.

Settlers of Catan in a browser tab, complete with the trade negotiations and the one player who will not give you wheat.

Match hue, saturation and complementary colours against a target, one exercise at a time, scored out of a hundred.