The harvesting of billions of larvae on fly farms, selling sterile male mosquitoes to prevent disease at the next soccer World Cup and turning a profit from "taking the piss out of Kenya".
If there's a sustainable future for life on Earth, it's in ventures such as these, says sustainability advocate Jason Drew, who focuses on turning waste into profit.
"There is no waste in this world," he says.
Drew presented a series of his revolutionary plans to an audience of students, academics and businessmen at the University of Johannesburg yesterday.
"We need to stop thinking of the industrial revolution and start thinking about the sustainability revolution," he said.
Drew - who sold all his conventional business interests in 2008 to start a fly farm in Tulbach, near Cape Town - believes the world is quickly running out of the natural resources we need to feed ourselves.
"Every single day, 375000 children are born and 175000 of us die. That means that, this evening, 205000 more people will sit down for supper than had breakfast this morning," he said.
He said that countries are depleting their biggest water resources - aquifers (underground reservoirs) - for agriculture and industrial use, and rivers are washing away crucial topsoil into the sea. The sea is being stripped by reckless fishing.
"In February, at the opening of the Japanese fish market in Fukushima, a single blue fin tuna sold for $1.8-million. That's three times the price of a rhino horn," he said.
Drew's solution is to set up companies that profit from exploiting the waste of humans and other animals.
He set up a fly farm in Stellenbosch at which he breeds fly larvae by spraying them with the "blood and guts" thrown away by abattoirs.
The larvae are turned into agricultural protein, replacing the fish meal and soya protein usually fed to fish and poultry.
"What we've built is the most extraordinary and unique factory in the world," he said.
Drew also started a company that sells sterile male mosquitoes to countries such as Brazil to prevent the spread of Dengue fever among those visiting soccer World Cup stadiums in 2014.
The male mosquitoes - which do not feed on human blood - mate with the disease-carrying female mosquitoes, causing them to lay eggs that will never hatch.
"We have sold 300million mosquitoes this year and next year we will sell a billion."
Drew also loves "taking the piss out of Kenya".
By supplying toilets to people living in that country's slums he created small self-sustaining businesses for some locals.
He harvests the urine and faeces from the toilets and sells them as liquid fertiliser and compost to Kenyan coffee plantations.
"Our urine fertiliser sells for $2.64 a litre. That is more than some of my neighbours sell their wine for," he said.
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