Many visioneers champion free markets, less government, fewer regulations and profits for those who test the technological envelope.

CNN: A pioneer in space and on Earth

So far, the company has built a one-eighth-size prototype to test its design, which consists of a carbon-fibre keel, an envelope made from modern composite materials, half-a-dozen engines, a passenger compartment, and a specially lightened crane.

ECONOMIST: Pushing the envelope