In theory, as everyone begins flying to work, flying cars could dwarf today’s $850 billion auto industry. The devices — ranging from air taxis to personal flying machines — could breathe life into aerospace companies’ growth or create a whole new generation of startups.

Air taxis, which would carry anywhere from four to eight passengers on shorter rides between smaller, now-underused airports, could become available in the next three to four years. Following in the footsteps of several startups, Honda has developed an experimental jet-powered air taxi, now in flight testing. In February, it announced it would manufacture, together with General Electric (GE ), the economical jet engine Honda developed for the plane. With $75 billion in annual sales, the Japanese carmaker could eventually enter the promising air-taxi business as well.

With air taxis whizzing overhead, personal flying cars’ arrival will only be a matter of time. If Robin Haynes has his way, they might even look a bit like the autos from The Jetsons. Haynes’ device, called the Skyblazer, will look like a car — and actually drive on the road — as well as fly. With a push of a button, wings will fold out of the car’s sides. “It’s like the ultimate engineering challenge to me,” Haynes says. “And I’d love to have one.”

More here.