Unicef's 'sweat machine' turns perspiration into drinkable water Created to promote a Unicef campaign in Sweden the device takes moistures from worn clothes, and spins and heats it to remove the sweat and then filters the remaining liquid so that only water molecules remain. It's inventors claim that the resulting product is actually cleaner than local tap water and that more than 1,000 people have "drunk other's sweat" in Gothenburg where the machine is currently set up. Designed and built by Swedish engineer and TV personality Andreas Hammar, Unicef hope the machine will highlight the fact that 780 million people in the world still lack access to any clean water. The main extraction component used to turn the sweat into drinkable water was developed by Hammar in collobration with The Royal Insitutue of Technology in Stockholm. ""It uses a technique called membrane distillation," said Hammar, "We use a substance that's a bit like Goretex that only lets steam through but keeps bacteria, salts, clothing fibres and other substances out." They have something similar on the [International] Space Station to treat astronaut's urine - but our machine was cheaper to build. The amount of water it produces depends on how sweaty the person is - but one person's T-shirt typically produces 10ml [0.3oz], roughly a mouthful. However, despite the machine's success in Sweden it seems like it could be put to more extensive use in the UK. Mattias Ronge, chief executive of Deportivo - the advertising agency that organized the campaign - said: "People haven't produced as much sweat as we hoped - right now the weather in Gothenburg is lousy." We've installed exercise bikes alongside the machine and volunteers are cycling like crazy. Even so, the demand for sweat is greater than the supply. Tell that to passengers on the tube.