The inventor of the computer mouse, Doug Engelbart, has died - having made little money from his creation.
Engelbart patented his idea in 1970, but mice did not come into widespread use until the Eighties - and he never received royalties.
The story of an inventor failing to cash in on a "big idea" is far from unique. The speakerphone, karaoke machine and the microchip were all ideas that should have made their creators rich - but didn't.
Here are 10 big ideas that failed to deliver for their inventors.
[Related: 10 tips to make your mobile's battery last longer]
American inventor Walter L Shaw died penniless, and at one point lived in a bus station - despite coming up with many of the ideas that underpin today’s telecoms. Shaw patented the speakerphone, among dozens of other ideas including conference calling and touch-tone dialling - but some patents expired before they were commercially viable, and Shaw’s employers failed to share profits with him. Frustrated, he devised “interception-proof” call boxes for the Mob, but they too failed to make him rich - he was found guilty of illegal phone usage in 1976.
The karaoke machine was invented in 1971, and has become wildly popular around the world - but its inventor, Daisuke Inoue, failed to patent his idea, feeling that he’d simply stuck existing technologies together for his hand-built “8-Juke” machines.
Time Magazine listed the inventor as one of its “Most Influential Asians”. Inoue is unrepentant. “When I see the happy faces of people singing karaoke, I’m delighted," he says.
The AK-47 assault rifle has sold more than all other assault rifles combined - with the cheap, easily manufactured rifle having sold an estimated 100 million around the world, legally and in counterfeit form. Its inventor, Mikhail Kalashnikov says he has never profited directly from his 1947 invention - he works, he claims, for the love of his country. He is unperturbed by the havoc wrought by his invention: "I sleep well. It's the politicians who are to blame for resorting to violence,” he says.
British engineer Geoffrey Dummer came up with the idea of the integrated circuit - what we know as the microchip - but having presented his idea at a conference in 1952, no company came forward with funds to help him build it. As a result, Texas Instruments patented a very similar idea six years later. “I have attributed it to war-weariness in one of my books,” Dummer said, “But the plain fact is that nobody would take the risk. The Americans took financial gambles, whereas this was very slow in this country”.
John Walker, the British chemist who invented the match in 1827 - by accident, while dipping a stick in a lighting mixture - refused to patent his invention, considering it “too trivial”, despite being urged to by friends such as physicist Michael Faraday. Walker did at least make some money from his invention - but it was rapidly copied, with rivals such as Samuel Jones launching exact copies - “Lucifers”, as opposed to Walker’s “Friction Lights” - by 1829.
Trevor Bayliss’s wind-up radio was designed to combat the spread of AIDS in Africa - by bringing communications to areas without electricity. He won an OBE for his work, but failed to protect his ideas - and described himself as “living in poverty” by 2013. “I was very foolish," says Bayliss. "I didn’t protect my product properly and allowed other people to take my product away. It is too easy to rip off other people’s ideas,” he said. Bayliss now campaigns for better protection for inventors.
Tetris kicked off the handheld gaming revolution - it was bundled with every Nintendo Game Boy sold, and has sold hundreds of millions of units on every gaming platform ever since. Its inventor, Alexei Pajitnov, did not receive a penny in the Eighties as Tetris-mania swept the globe - the game was “owned” by his employer, the Soviet government. "You could always make a little more,” he says, “but I never seriously think about this stuff. I live as I live."
The Hungarian journalist who invented the Biro pen - Laszlo Biro - sold the patent for his invention in 1950, just before the pens dropped in price and became mass market items used in schools. The Bic Cristal - based on his idea - has since sold more than 100 billion units, and sells more than 14 million a day.
The inventor of the magnetic strip found on most credit cards “never made much money” from his 1969 patent, he admits. Ron Klein’s invention used the magnetic tape from computers to speed up the process of checking credit from “minutes” to “seconds” - prior to his idea, cashiers had to check credit cards against a book of “bad” numbers they were sent every month.
It’s the ancestor of today’s action videogames - but the designers of Spacewar never made anything from it. Designed in 1962 at MIT, and running on a PDP-1 'minicomputer' the size of a fridge, Space War pitted two players against one another in a spaceship battle - the game was written by four students, and shared widely, but never sold. ''The only money I made from Spacewar was as a consultant for lawsuits in the video game industry in the 1970's. I have all this fame, but it's in a very narrow circle,” said designer Alan Kotok.