Bike makes riders high-flyers, if only for five minutes
Flying cars are yet to take off - could bikes have a better chance?
Researchers in the Czech Republic have unveiled a 95kg (210lb) remotely-controlled bicycle that can hover a few metres above ground for five minutes.
Carrying a dummy rider, the electric prototype successfully took off, flew around and landed inside an exhibition hall in Prague.
The bike is powered by two battery-run propellers on the front, two on the back and one on each side.
The machine could help two-wheeled commuters avoid zigzagging through traffic jams - but it is not quite ready to hit the road - or the air above it - just yet.
The batteries only allow for a few minutes of flight before needing to be re-charged.
"Because the capacity of batteries doubles about every 10 years, we can expect that in the future the capacity would be enough for the bike to used for sports, tourism or similar things," said the technical director of Duratec Bicycles, Milan Duchek.
To create the bike, Duratec worked together with two other Czech firms, Technodat and Evektor.
Bikes with parachutes
It is not the first attempt to make a bicycle fly.
In August 2009, an IT teacher John Carver from Oxfordshire constructed what he called the "Flyke" - a flying tricycle - and flew it across the UK, from Lands End to John o'Groats, for charity.
Registered with the Civil Aviation Authority, Mr Carver's machine is powered by a two-stroke twin propeller motor with a paraglider canopy.
The bike has to be refuelled about every two hours, is able to carry up to 25.4kg (56lb) of luggage, and can reach a flying speed of about 32km/h (20mph). According to Mr Carver's website, the device is now for sale.
Companies such as Para-Cycle sell similar devices as well, but a huge parachute may prove cumbersome for the city commuter.
And in the early 20th Century, among the very first "flying machines" were bicycles with wings attached to the frame - what became known as aviettes.
They did not really fly, but rather hopped above ground, or glided, having been first powered by fierce pedalling.