Dearman's failed liquid-air car engine found its market as a zero-emission fridge
Peter Dearman's engine ran on liquid nitrogen; when cars proved hopeless, Toby Peters realized the exhaust's cold was the product, not the power.
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500 PUBLISHED CASES · REGULARLY UPDATEDDan Egan charges cold-emailers a $20 deposit that only clears if he replies
From Marc Andreessen's $100-per-email idea, a behavioral-finance expert made strangers post a refundable charity deposit before he'd read their message.
Read the caseCalifornia pays meth and cocaine patients gift cards for clean drug tests
Escalating gift cards for negative drug tests is twice as effective as counseling — and California is now the first state to pay for it with Medicaid.
Read the caseColaLife rode Coca-Cola's distribution to put anti-diarrhea kits in Zambian villages
Simon Berry designed a Kit-of-Life to fit Coke crates' dead space — then found the real hack was Coke's wholesaler economics, which any product can ride.
Read the caseCellophane let supermarkets sell meat by sight — self-service retail took off
Moisture-proof, oxygen-calibrated film cleared the last barrier to self-service groceries — the discolouring meat counter — and reshaped how food is sold.
Read the caseCarbon Lighthouse guaranteed building energy savings, then let software skim the waste
Two physicists sold building owners the money their waste was worth, backed it with a written guarantee, and let AI retune systems every five minutes.
Read the caseA California 'Costco for heat pumps' cuts equipment costs 15–30% with group buys
Vayu and VoltHub's California Heat Pump Group Buy pools households for bulk discounts — installers get a queue of jobs and heat waves do the marketing.
Read the caseBoston put Moving Day van permits online by skinning its legacy system, not rebuilding
Boston's tech department pre-screened van permits itself and layered a portal over its rigid back end — 1,200+ people applied online the first Moving Day.
Read the caseGearbox hid a DNA-science puzzle inside Borderlands 3 and 4M players mapped the microbiome
A tile puzzle hidden inside a AAA shooter turned 4 million gamers into microbiome mappers — half a day beat a decade of standalone effort.
Read the caseBlock by Block has residents design real public spaces in Minecraft — then builds them
UN-Habitat, Microsoft and Mojang's venture turns consultation into play: 17,000+ participants in ~100 countries, one project a Gaza community garden.
Read the caseBlackbird, a propeller cart, raced directly downwind at 2.8x wind speed and won
A wind-powered cart with its propeller geared to its wheels outran the wind blowing behind it — an idea 99% of people call impossible.
Read the caseA sob story about a dead grandma's locket made Bing Chat solve a CAPTCHA
Denis Shiryaev pasted a refused CAPTCHA into a photo of an open locket and added a grief story; reframed as a keepsake inscription, Bing Chat read the text out.
Read the caseBicitekas rescued Uber's condemned Jump bikes at one peso each — 1,600 reborn
A Mexico City nonprofit bought the condemned fleet for a peso apiece, stripped the licensed tech, and made the shells fund their own rebirth as loaner bikes.
Read the caseBAYCAT's studio pays for its school: a nonprofit run like a two-sided business
Villy Wang's BAYCAT pairs a free digital-media academy for underserved youth with a paying client studio, so the mission funds itself instead of chasing grants.
Read the caseNeeding a bigger win, Barbados scored a deliberate own goal — and won on a golden goal
Trailing 2-1 with seven minutes left and needing a two-goal win, Barbados equalised into its own net, then won extra time on a golden goal worth two.
Read the caseBaptist Health made money on hip and knee replacements by spending less on each one
Medicare paid a lump sum per joint-replacement episode; Baptist and its surgeons kept the savings — so cutting care became the profitable move.
Read the caseBagan IT billed unbanked Myanmar via telco bills and sold via repair shops (interview)
In a country where 75% are unbanked and data gets switched off, Bagan IT built payments, support and trust out of telcos, tuck shops and no-questions refunds.
Read the caseArgentina'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.
Read the caseApple'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.
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