Rabbit hole

Over a hundred thousand high-resolution scanned maps, georeferenced and free to zoom into more or less indefinitely.

Field reports and photographs of American shopping centres in decline, written by people who cared about this long before it was an aesthetic.

One search across thousands of American libraries, archives and museums, with curated exhibitions layered on top.

The catalogue of every physical release ever pressed, down to matrix numbers and pressing variants, plus what your copy is worth.

Ankh-Morpork rendered as a text world, with guilds, working shops and an obsessive attention to what Pratchett actually wrote.

Machine learning journal where every paper is an interactive diagram; publication has stopped, the back catalogue has not aged.

Single-player browser RPG from the AdventureQuest studio, with a long story campaign and jokes aimed squarely at 2007.

Isometric hack-and-slash that runs in the browser and does a competent impression of Diablo with nothing to install.

A directory that has been curating this genre since 2004, including a great many games nobody else bothered to archive.

Yu-Gi-Oh played manually against real opponents, with every card ever printed and no automation to hide your mistakes.

A fantasy city builder with elves, humans and a genuine research tree, played entirely in a browser tab and unusually pretty.

A simulated 1990s desktop with a working browser, games and applications, assembled as a preservation project rather than a joke.

A daily firehose of new escape games from Japanese and indie developers, with walkthroughs in the comments for when you stall.

Fifty million digitised items from European museums, libraries and archives, behind one search box.

A scatterplot of six thousand music genres you have never heard of, each one clickable for a sample and a list of its bands.

Writing community from 1999 where each subject gets personal essays instead of an encyclopaedia entry, and the tone never settles.

Idle evolution from primordial soup to interstellar empire, with dozens of species branches and an enormous technology tree.

Hundreds of playful projects from Google and creative coders: AI drawing games, music toys and odd interfaces, most of them running in the browser.

The hub for playable posts — effectively the index for the entire genre of learn-by-fiddling essays.

An idle game built on actual differential equations, with optional theory levels that teach you the mathematics as you climb.

London has been dragged underground by bats, and the writing is far better than that sentence suggests. Free, endless, faintly sinister.

Tens of thousands of fan-run wikis, each documenting one fictional universe in wholly unreasonable depth.

A preservation project that has rescued more than a hundred thousand Flash games and animations from deletion, all playable.

The two-person studio behind the entire Papa's restaurant series, with the back catalogue and the odd non-cooking game too.

City building from the Stone Age to the near future, with a tactical battle grid and guilds fighting over a shared continent.

Street-level archaeology of the city — old lamp posts, painted signs and vanished railways, walked and documented since 1999.

A long, community-kept list of software and services with genuinely free tiers: hosting, databases, email, monitoring and much more.

Long-form expeditions into Japan's abandoned mines, hotels and theme parks, written by somebody who actually climbed in.

A hosting hub for hundreds of amateur incremental games, sorted and playable in the page. Where the genre does its experiments.

The French national library's digital collection — manuscripts, maps, newspapers and photographs, millions of items deep.

Part indie games host, part social network, where horror fan games and unfinished experiments live cheerfully side by side.

A browsable restoration of the GeoCities neighbourhoods, so you can wander into Area51 or SunsetStrip the way people once did.

Directory of the emptied-out settlements of the American West, one short paragraph and one faded photograph at a time.

Long-running newsletter and link hoard for glitch art — tools, artists and the occasional genuinely disquieting find.

Curated wall of the best-designed sites on the internet, filterable by type and updated relentlessly.

Castle building and siege warfare with the exact aesthetics of an advert you have definitely been served, and better strategy underneath.

Tim Rowett's collection of optical toys and physics oddities, each demonstrated on camera by a man visibly delighted with all of it.

A boarding-school story with robots, forest gods and a plot that has been quietly paying things off since 2005.

Daily coverage of hardware projects that had no commercial reason to exist. Reliably the most inventive corner of the web.

Grey text on beige, no images, and the best comment threads anywhere about how technical things actually work. Search covers twenty years.

Football management one week at a time since 1997, with a transfer market and an economy run entirely by other managers.

Tens of thousands of hosted model demos, each running in a browser tab. The closest thing machine learning has to an arcade.

Charts and datasets tracking long-run trends in health, income and violence, useful ammunition for pessimistic dinner parties.

Allie Brosh's illustrated essays, including the two on depression that remain the best thing written about it.

Post-apocalyptic comedy RPG with turn-based fights, base building and a tone somewhere between Douglas Adams and a mild fever.

Every plant and animal anybody has photographed and posted, mapped, with a community that will identify your mystery beetle within hours.

The wiki of a movement for owning your own website: guides, tools and real examples of people publishing on their own domains.

Numbers-heavy tower defence with endless mode, research trees and the general energy of a very well-kept spreadsheet.