ciechanow.ski
The best thing on the web, and it isn't close. Each essay takes one topic — gears, the GPS, light and shadow — and builds a playable mental model of it. Every diagram is a live simulation you can drag. No ads, no newsletter popup, no "5 things" One post every few months because each takes months The sailing one finally made me understand how boats go upwind It's what the web was supposed to be.
everynoise.com
A single page that plots every genre Spotify has a name for onto one scatter map — down and left is denser and more atmospheric, up and right is spikier and bouncier. Click anything and it plays. wonky, escape room, vapor twitch, deep discofox — genres you didn't know had names, arranged so neighbours actually sound like neighbours. The whole thing is one guy's side project running off Spotify's audioanalysis data. I've lost whole evenings just wandering it.