With people traveling more and more for business and vacation, and the cost of travel rising at a steady rate with no real solution on the horizon, its time to look at our options for possible future alternatives.
Now, the ideas that have come up are not new. One is to create more public transit, including trains, cable cars, and buses. I call this the "Public Expansion" (or PE) option. The other is the Increased Vehicle Efficiency (or IVE) option. This is one that we are most familiar with, as it pertains to our cars, trucks, and motorcycles. Its the idea keeping the current motor and road system, but adding efficiencies to the existing fuel or vehicle, or by creating new fuels. This is where MPG standards, hybrids, hydrogen fuel, and Biodiesel come in. There is a third option, that is not new, but is not often considered. This would be a hybrid between the two systems, called "Personal Rapid Transit" (or PRT).
This is what wikipedia has on them:
Here is a video with a good explanation.
This is a hanging style that I personally prefer and (though more complex) solves a lot of problems of the other current versions.
Essentially, this hybrid system would be the best of both worlds, and as such would solve a lot of the current and future transportation problems. Although there are a lot of technological and infrastructure hurdles to overcome. It is still a great idea, and one that is being taken more and more seriously over time.