Cool software,
found for you.

An interactive article on elevator scheduling — SCAN, LOOK, Otis' RSR, and destination dispatch — with live simulations you can speed up, add traffic to, and benchmark side by side. Ends with a full sandbox sim where you set floors, cars, flow rate and algorithm.

The best kind of explainer — you don't read the conclusion, you watch it happen. The counterintuitive bit is that those fancy destination-dispatch kiosks usually make waits worse, because they lock you into one car and the system can't re-optimize. Hard to stop fiddling with the final sim.

A crowdsourced US map of meals under $10. People drop spots with prices, vote, and comment; you browse by city or pan the map. No chain restaurants and no sponsored placements.

Crowdsourced maps live or die on contributions, and this one looks alive — the newest entries were price-verified within the last 48 hours. Houston, Chicago and Philly are deepest. US-only, so skip it if you're elsewhere. The maker commits 10% of profits to food banks and promises quarterly numbers.

A plain-text weather forecast — 7-day table, hourly conditions, and ASCII charts for precipitation, temperature/humidity, UV, air quality and pollen. Search any location. Data from Open-Meteo.

Faster to read than any weather app, and the ASCII precipitation chart is genuinely clearer than a radar loop. Made by one person in York. The pollen and air-quality rows are a real addition, not filler, if either affects you.

Indexes HN links submitted repeatedly by different people over many years — 1,176 in the Hall plus 1,995 candidates. Each entry shows full submission history, peak points, and when it last resurfaced. Browse by type, topic, or induction class.

A reading list built from what endures rather than what's trending. The induction rule is published openly — five-plus submissions from three-plus people across three-plus years — which is why I trust the list. Unaffiliated with YC. Start with "recently resurfaced."

A browser visualization of a black hole, described by its author as a simplified version of Synchray.jl — his open-source special-relativistic raytracer for synchrotron emission from astrophysical jets.

Made by an astrophysicist as a side project spun off his actual research code, which is the whole appeal — the toy has a serious engine underneath. Give it a moment to load.

A free, searchable marketplace indexing 32,000+ products from 60+ worker-owned and employee-owned companies across eleven categories — coffee, food, apparel, books, beer, art, home goods, personal care, music, games, software. Also has a locator for worker-owned cafes and restaurants near you.

Refreshingly not a storefront — it links out to the companies' own sites and takes no commission, which is the main reason I trust the list. The "Instead of Amazon / Etsy / Spotify" guides are the fastest way in. US-focused, so less useful elsewhere.

Reconstructs real-time London Underground train positions from TfL open data and lets you board one and ride it through a 3D model of the city.

The novelty is the seat, not the map — you're on a specific train, right now, moving. Good if you miss the commute, or never had one. It loads a fair amount of 3D, so give it a moment on a phone.

An open-source map of displaced cultural artifacts, drawing an arc from each object's origin site to the institution now holding it. Browse by country, institution, or collection.

The arcs make the argument faster than an essay could — you see the direction of travel immediately. Useful if you follow repatriation debates, and quietly sobering if you don't.