Argentina's foreign tourist dollar gave foreigners double the pesos locals got
To catch scarce dollars, Argentina's central bank let foreign cardholders exchange at near-black-market rates — twice what locals could officially get.
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1,000 PUBLISHED CASES · REGULARLY UPDATEDApple's Find My crowdsources your lost laptop's location — and even Apple can't see it
Find My turns every nearby iPhone into an anonymous relay for your stolen device's location, encrypted so that not even Apple can decrypt it.
Read the caseAeroVelo's optimizer designed Atlas to take the 33-year human-powered helicopter prize
A team that knew nothing about helicopters dropped the gym-size constraint, modeled everything and let an optimizer design the winning craft on a laptop.
Read the caseYichang made buses faster by redesigning the street around them
Yichang's BRT treated lanes, parking, sidewalks and driver training as one operating system.
Read the caseVietnam electrified the countryside by letting locals build the grid, then merging it
Vietnam's rural electrification went from 14% in 1993 to 99% in 2018 by letting locals build the last mile, then merging it into the national utility.
Read the caseSouthwest locked in fuel prices years early and flew through the spikes
While rivals paid spot prices, Southwest hedged jet fuel years ahead with options and collars, saving over $3.5B across the oil-shock decade.
Read the caseMIT taught a CAD-generating AI by feeding it its own near-misses
MIT's GIFT targets training data at a model's own 50%-right failures instead of random augmentation
Read the caseJBL turned head-tracking audio into echolocation so visually impaired gamers can play
JBL proved its Quantum spatial audio with software that turns on-screen game action into directional sound, letting blind gamers play by ear.
Read the caseW. L. Gore stretched PTFE fast to make a membrane both porous and stronger
Gore's 1976 patent showed speed itself was the parameter: stretched hard enough, PTFE turned porous and stronger at once, and became Gore-Tex.
Read the caseDaniel Patterson rebuilt Gmail from open-source parts; only tagged mail reached his phone
Daniel Patterson assembled Debian, notmuch, afew and K-9 Mail into a Gmail replacement where tags drive search and only tagged mail is pushed to his phone
Read the caseThe EU made imports pay the same carbon price as home-made steel
From 2026 importers of steel, cement and fertiliser buy certificates priced off EU ETS auctions, so moving production abroad cannot escape the carbon price.
Read the caseCoca-Cola paid viewers to spot its own product placements with an Alexa skill
Coca-Cola Middle East turned decades of product placement into a game: say 'Alexa, I see Coke' when one appears on screen and win an instant discount.
Read the caseCloudflare gave every Git branch its own isolated production-like environment
Instead of one shared staging site, Cloudflare Worker Previews spin up a full isolated environment, including its own Durable Object namespace, per branch.
Read the caseChabris caught Gladwell's font claim on a 40-student study that never replicated
When Gladwell wrote that hard-to-read fonts boost reasoning, Chabris opened the cited paper: 20 Princeton students per font — wider tests failed to replicate
Read the caseeSpark used TLA+ to prove no design met all 3 rules, then traded one away
Before coding a risky config-automation system, eSpark modeled it in TLA+, found every design failed, and used the proof to negotiate down a requirement.
Read the caseSoundCloud tested every JVMKit release against all its dependent services first
SoundCloud built a reverse dependency graph so every shared-library release compiles and tests against every caller before shipping.
Read the caseSoundCloud replaced 100 undocumented ETLs with six-principle data governance
SoundCloud's Corpus team rebuilt its data warehouse on BigQuery around six written principles instead of just moving tables.
Read the caseRamp replaced per-worker Celery rate limits with one global Redis rate limiter
Ramp scrapped per-worker Celery rate limiting for a global GCRA limiter on Redis that stayed accurate as workers scaled.
Read the caseGoogle let an AI agent playtest its own generated classroom simulations before release
Google Research built generative UI for teachers, then had an agent open a browser and try to break each simulation before any human saw it.
Read the caseCloudflare split HTTP's Vary header into what varies and how much matters
Cloudflare let origins declare which headers affect a response while Cache Rules decide how much of each header's variation is worth a separate cache entry.
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