Which is more likely, flying cars or flying pigs?

It seems to be the week of flying cars: is it madness or is there something in it?

When the NASDAQ Composite passed 5,000 during the height of the dotcom bubble, it turned out that it was a bubble inflated on hype. The index has now passed 6,000, and frankly there does seem to be good reasons for the new high, this time. But, maybe the spat of rumours about flying cars points to bubble like behaviour, or maybe just hot air – literally.

First off, we had the news that a company called Lilium announced its all electric, vertical take-off plane/car; it seemed almost too good to be true.

The Lilium Jet

Science fiction, from 1960s kids cartoon the Jetsons, to sci fi movies such as the Fifth Element, suggested that in the near future the skies would be full of cars. But, as Peter Thiel, co-founder of PayPal famously said: “We wanted flying cars, instead we got 140 characters.”

Instead of flying cars we got cars that drive along that flattish thing, we call the ground, and we got a very unfortunate form of jam – traffic jam.

But now it has emerged that Larry Page, the Google co-founder, and chief executive of a wee company called Alphabet, is backing a Silicon Valley start-up called Kitty Hawk. Its product looks a little like the wings on Chitty Chitty Bang Bang, but that is about it.

But the sheer fact that Mr Page is on board speaks volumes.

But now Uber has joined the fray, announcing a project called elevate. The idea is for flying taxis – actually Lilium proposes a similar concept. Uber has got ideas for vertiports, and plans to test its idea in Dubai and Texas.

A prototype is slated for the World Expo 2020 in Dubai. Jeff Holden, the company's chief product officer said: "It's natural for Uber to turn our eyes to the air. Push a button and get a flight."

But there are other players.

There is Terrafugia, for example, Ehang, and the Volocopter.

There is also an obscure airline called AirBus that has plans too.

When so many companies are working on similar concepts, it rather begs the question is there anything in it?

Is this a realistic idea, a product for the rich only – something Lilium says is not the case – or are flying pigs more likely?