A toilet to process human waste into clean water and even energy is being developed by UK university researchers.
The "nano membrane toilet" project is funded by the Bill and Melinda Gates Foundation and work is being done at Cranfield University in Bedfordshire.
Researchers said the unit could help bring sanitation into the homes of 2.5bn people in developing countries.
The system does not need water supplies or sewage pipes and generates enough energy to charge a mobile phone.
It could also be used by the military or in luxury yachts, the construction industry or at music festivals, researchers said.
PhD student Jake Larsson said a major cause of disease in developing countries is inadequate sanitation and the nano membrane toilet could help combat that.
"It is a household scale toilet that produces clean water and manageable, pathogen-free, disposable waste."
The toilet is activated when the lid is closed, carrying the waste into a holding tank.
The "nano membrane" only allows water molecules through with solid waste and pathogens passing into a gasifier which burns it to produce an agricultural quality ash.
The water is suitable for irrigation or washing and could even be made clean enough to drink.
Heat from burning the waste produces enough electricity to power the unit, and could even produce a extra for mobile phone charging.
The Cranfield University team aims to start field testing in 2016 and the toilet would be rented for 3p per day.
The scheme won an "excellence in the field of environmental technology research" award at the recent CleanEquity Monaco conference.