(CNN) -- It is almost 100 years since Henry Ford's young motoring company launched the Model-T, the car that "put America on wheels" and triggered a revolution in human mobility.
The 20th century belonged to the motor car. Towns and cities were reconfigured to accommodate the needs of the growing army of motorists, spawning suburban sprawl, commuter belts and drive-thru Dunkin' Donuts.
When Aldous Huxley was looking for a godlike technological totem for his futuristic fantasy "Brave New World" he chose Ford. The world was heading for autopia.
But attitudes have changed. Car ownership is no longer consequence-free. On Wednesday California, the spiritual home of the freeway, announced it was suing six automakers, including General Motors, Toyota and Ford, over damage caused by the greenhouse gas emissions from their vehicles.
The move forms part of state governor and self-confessed Humvee addict Arnold Schwarzenegger's campaign to place the West Coast state in the forefront of the fight against climate change.
"Global warming is causing significant harm," said State Attorney-General Bill Lockyer. "The impacts are already costing millions of dollars and the price tag is increasing. It is time to hold these companies responsible for their contribution to this crisis."
Environmental concerns are not the auto industry's only problem. Rising oil prices have sent motoring costs spiraling while congestion in many cities is now so bad that average speeds have dropped below what they were in the golden age of the stagecoach.
The motor car is statistically also the most dangerous mode of transport with an estimated 1.2 million people killed and another 40 times that number injured in accidents each year. So has our love affair with the automobile reached the end of the road?
Hilton Holloway, Associate Editor of Autocar, the world's oldest motoring magazine, doesn't think so. He says the motor car has plenty left of gas left in the tank, but predicts that tank is more likely to contain hydrogen than gasoline.
BMW has said it will start producing hydrogen-powered cars, which emit nothing other than water, in 2007 and Holloway recently tested GM's fuel cell-driven Sequel in California, a vehicle the company hopes to roll out across the market in 2010.
"They're quite serious about this," Holloway told CNN. "But it just takes a massive movement where everybody has to just line up and say this is what we're going to do to put the infrastructure in place."
He said the costs of emissions regulations in California were so high that hydrogen-powered cars, which emit nothing more damaging than water, would become increasingly attractive as costs came down.
"We will see a tipping point in about five years when environmental regulations put up the cost of producing an internal combustion engine to the point where its worth switching to hydrogen. They're clearly close to being able to produce a car at a price which people are able to afford."
California's efforts to cut back the auto industry's greenhouse gas emissions are not the first time it has acted to regulate the motor industry, with past innovations introduced in the state including airbags and smog-busting catalytic converters.
But Holloway said the car industry was more responsible than in the past and said a better approach would have been to ban cars that do less than 24 miles to the gallon and by promoting low-emission PZEV (Partial Zero Emissions Vehicle) models.
"Back in the 1970s the car industry had to be kicked into doing things. Now I think it's done most of what has been asked of it. Cars are a lot safer and immensely cleaner. The problem is if the customer doesn't buy the Ford Focus PZEV and he buys an Offroad Ford Ranger instead, who's fault is that?"
While hydrogen fuel cells may not kill off the internal combustion engine until well into the next decade there is already a movement towards building cleaner cars.
In Brazil more than two million vehicles, 77 percent of the market, run on ethanol, known as Flex-Fuel, created from sugar cane. The use of biofuels is also gradually increasing elsewhere in the world.
"That's a great intermediate solution between now and hydrogen," said Holloway. "But you have to grow a lot of plant life to make it."
But while the technology may exist to keep the motor car alive for another century, could it one day be replaced by a new form of transport, just as it once supplanted the train and the horse?
Segway inventor Dean Kamen believes the demands of growing urban populations pose the next challenge in transport technology.
"The next generation is going to need something for its pedestrians in the same way Henry Ford invented something for people moving out of the cities. The city needs a car like a fish needs a bicycle." Kamen told CNN last year.
Holloway admitted motoring may have peaked in the U.S. and western Europe but said it was in developing countries such as China and India that the real market for new cars would be.
In a sign of things to come, Toyota, the world's second-largest automaker, announced in July it was doubling production at its Shanghai factory to meet growing Chinese demand.
"You can't even begin to imagine the development in China -- it's mind-boggling," said Holloway. "Only six percent of people in India have a car. That's where the next great expansion will come."
Holy Gee,
Cars powered by water
Image the money you'd save on THAT!
They might say "You can only refuel your car once every x weeks 
