Rolls-RoyceUber, and Google's own Larry Page picture a near future where people will be flagging down cabs from the sky rather than the street. You might encouraged to look into it yourself. Maybe it's your next great business idea.

It's not. Such visionary predictions tend to overlook the fact that our cities, infrastructure, and general social lives aren't quite ready for a Back to the Future Part II souped-up DeLorean. Certainly, some flying cars may be available on the market for one-percenters with deep pockets and a need for expensive playthings. For most people, though, the plane-car hybrid will remain a futuristic fantasy item for the foreseeable future.

What's the problem with a winged car? In the first place, it's highly unaffordable. Like most new technologies, a flying Tesla or Ford is bound to be priced to make even Lamborghinis seem like something you'd get at a roadside used car lot. While some proponents, including Uber, have said fares to fly would be low, it's difficult to imagine that being the case. The AeroMobil 4.0, for example, has a pre-order price of $1.3-1.6 million. How could companies afford to purchase and maintain these flying taxis if they charge rock-bottom prices?

Besides, the roadways--airways?--aren't nearly prepared for flying cars. How will their flight patterns be directed, and by whom? Right now, cars drive on the road, and planes fly in airspace. Adding a mode of transportation that's in between will require endless regulations and decisions. Transportation officials have full plates already; adding to the mix cars that zoom below or into the clouds is going to complicate matters in the extreme.

In 20 or 30 years, the world may have a different view of this bold new approach to commuting from point to point. But for now, the flying car remains nothing more than a billionaire's toy. Meanwhile, other transport ideas have emerged that may provide a bridge between today's surface-bound paradigm and a flight-worthy tomorrow.

Don't waste your time starting a business that depends on the flying car. Instead, consider focusing your next venture on one of these three more useful transportation trends:

1. Cars that do the driving for you

Why invest in a car with wings when you can just hop into an autonomous vehicle? Self-driving cars are being tested by a variety of companies and customers. Uber in particular seems to be taking a full-steam-ahead approach.

Of course, having no one behind the wheel means relying on the vehicle's sensors, as well as the reflexes of a remote human (for now) driver. Already, reports of accidents involving driverless cars have prompted skepticism regarding the safety of such vehicles.

At the same time, champions of this leading-edge technology note that the majority of roadway accidents are caused by human error and argue that artificial intelligence can help lower fatalities and injuries related to driver fatigue, distraction, drunkenness, and other factors. Certainly, concerns associated with autonomous vehicles can sooner be addressed than the myriad issues raised by the flying car.

2. Bullet trains that "fly" with magnetic help

You've probably heard the phrases "hyperloop" and "Elon Musk" together. What does it actually mean?

A hyperloop is a space-age invention that could potentially take passengers from one place to another at speeds of up to 760 miles per hour. It works through the power of electric magnets.

The hyperloop isn't without its cons. Despite its promise of speed and and efficiency, it requires serious capital to develop. Its routes must be fairly straight, and even then, you'll be buckled into your seat and unable to move during operation. Still, those are pretty minor challenges when compared with flying cars.

3. Bicycle highways for all-weather transport

Imagine jumping on a bike and practically flying to work without worrying about motorized vehicles, pedestrians, pollution, or Mother Nature's wrath. Bicycle highways built entirely for cyclists's needs would ideally be enclosed tunnels with plenty of light and room to safely navigate.

Such highways would ease your morning commute, and cycling to work could take inches off your waistline. After all, an hour of pedaling consumes anywhere from about 280-600 calories for the average-sized rider.

Obviously, infrastructure requirements and expense present hurdles to making this vision a reality. However, it's not out of the realm of possibility, particularly in metropolitan areas with large cycling populations.

No matter your attitude toward the flying car, you probably won't be reaching any altitudes in them for at least a generation. Never mind, though: There are other options that won't make you wait nearly as long to reimagine your travels.