"By 2050, the capitalist system is going to be totally transformed," he claimed, speaking via webcast from Spain. In Rifkin's idealized future, less and less of us will own cars, toys or other consumer goods -- we'll share them instead. Ultra-efficient 3D printers will replace our wasteful factories. Oil, coal and gas will give way to solar, wind and geothermal. And all of this will be linked through an "Internet of things" that may allow us to radically lower humankind's ecological footprint.