NYC subway listens for broken rails with six Google Pixel phones
The MTA strapped six Pixels under A-train cars: 335M readings and 1,200 hours of audio trained ~200 models that flagged 92% of defects inspectors found.
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500 PUBLISHED CASES · REGULARLY UPDATEDCamden found its costliest patients by crime-mapping hospital billing data
A family doctor borrowed police Compstat for medicine: map billing records, find the 1% driving a third of costs — 36 super-utilizers cut bills 56%.
Read the caseReward blood donors for showing up, not giving — incentives without lying
Paying for showing up kept screening honest: gift cards and paid leave raised donations up to 40% with zero measurable damage to blood-supply safety.
Read the caseBART hired Pac-Man the hawk — pigeons halved in a week without touching a nest
After spikes, netting, owl statues and noise failed, BART flew a Harris's hawk three days a week; instinct scattered the pigeons for it.
Read the caseAmsterdam paid street-cleaning alcoholics in beer — streets clean, park crime down
The Rainbow Group hired 20 chronic alcoholics for 09:00–15:00 litter shifts with beer breaks; police reports of stabbings and muggings in Oosterpark fell.
Read the caseSunamp turned the hand-warmer's phase-change gel into a heat battery in 650 homes
A heat exchanger in phase-change gel stores solar heat and gives instant hot water when cold water triggers crystallisation — at about half the cost of gas.
Read the caseVW's Speed Camera Lottery paid safe drivers from speeders' fines — 32 to 25 km/h
A contest idea entered law-abiding drivers in a lottery funded by speeders' fines; Stockholm's test saw average speed fall 7 km/h in three days.
Read the caseMás Fresco matched food-stamp dollars on fresh produce one-to-one
USDA-funded researchers gave SNAP shoppers up to $40 in produce matches at a Latino grocery chain, testing which dollar level actually changes diets.
Read the caseAWS replaced fat-tree datacenter networks with a quasi-random graph — and deployed it
AWS's resilient network graphs flatten the datacenter into a random-ish pool of paths; a ShuffleBox tames the cabling — 69% fewer switches, 40% less power.
Read the caseAmsterdam's painter-inventor cut fire losses by 99% with a leather hose
Jan van der Heyden paired a better pump and a flexible 'snake' hose with alarm rules and arrival prizes — fire losses fell below 1% of the old level.
Read the caseTwo mathematicians broke SIKE post-quantum crypto in an hour on a single PC
KU Leuven researchers exploited SIDH's known-degree isogeny and auxiliary points to recover SIKE keys on one traditional core, knocking a NIST alternate out.
Read the caseA teen's low-frequency cave radio texted through 1,000 feet of New Mexico rock
Sixteen-year-old Alexander Kendrick's device sent a text from 946 feet underground — rescue communication without laying miles of telephone wire.
Read the caseHeata bolts cloud servers onto home boilers so computing heat becomes free hot water
The UK startup Heata hangs cloud servers on household water cylinders: firms buy the computing, families keep the heat — about £250 of hot water a year.
Read the caseWhen Cash WinFall's jackpot rolled down, one couple bought $614K for a sure thing
A Massachusetts game's roll-down rule briefly made every ticket profitable; the Selbees' firm bought $614,000 across two stores and waited for the math.
Read the caseSenegal's text-message auction undercut Dakar's septic-vacuum cartel — prices fell 7%
A call center texted each septic job to a dozen truckers as a live reverse auction, breaking a cartel that charged $40–60 a tank — prices fell 7%.
Read the caseA Dutch lab flew a rudderless drone by giving it pigeon reflexes
David Lentink's PigeonBot II stabilizes without a vertical tail: morphing wings and a reflex controller do the rudder's job, the way birds do it.
Read the caseA 3D-printed fake turtle egg with a phone inside mapped the egg-poaching trade
Paso Pacífico hid a cell-connected GPS tracker in a squishy printed egg: poachers carried it into their own trade and exposed a local, door-to-door market.
Read the caseAWS's Ocelot chip bakes error resistance into qubits, cutting correction costs up to 90%
Instead of correcting quantum errors after the fact, AWS engineered cat qubits that resist them in hardware — cutting error-correction costs by up to 90%.
Read the caseThe Witcher 3 priced its whole economy with polynomial least squares curves
With no working economy months from release, CD Projekt Red's designer tuned price curves with least squares and shipped the coefficients, not prices.
Read the caseWeChat ran creator tips at scale years before Medium — until Apple shut it on iPhone
Ten percent of WeChat users tipped writers, at least $52M a month — until Apple's IAP rules killed the button on iOS in April 2017.
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