As adaptive cruise controls, self-parking options and automated-braking systems gradually become more capable and widespread, it is not a big leap to full autonomous control.

ECONOMIST: Inside story

As if that wasn't enough, the whole thing also promises to be funded entirely by micro-payments from the public (which would also determine its final size), and be completely self-powered, with it relying on a combination of solar power and regenerative braking from the lifts in the towers.

ENGADGET: Digital 'Cloud' could form over London for the 2012 Olympics