I'm a big believer in public transportation. I generally believe that the only way to build a big, efficient, and sustainable city is on the backbone of a good transit system. But at the same time, I'm open to fresh ideas. And I'm concerned with the inability of most cities to actually build transit in a way that meaningfully responds to demand.

So what are the alternatives?

The first thought that comes to mind is the delivery system itself. Some cities, such as Hong Kong, have successfully combined transit delivery with real estate development as a way to improve the economics behind building transit. And I think that makes a lot of sense.

But my other thought is that maybe the solution to urban mobility is something completely new. Maybe Google is on to something with their driverless cars. Is that the future? Many would disagree.

We've established that cars don't work all that well for getting people around in big congested cities. So what difference would it make whether or not the cars have a driver or not? Well, I was thinking about this last night and there are some meaningful differences.

A network of driverless cars would give us perfect information about all to the cars on the road. Similar to to how Google's Waze navigation app feeds off user input (both active and passive), we'd know the exact number of cars on the road and the precise point in which additional cars would cause a drop in efficiency (i.e. a reduction in vehicle speeds).

At the same time, it could enable a powerful sharing economy. In a recent study done by MIT's Senseable City Lab, it was found that roughly 80% of New York cab rides could be shared. That is, 80% of the time there's somebody else who's also traveling from roughly the same point A to the same point B.

So here's what I'm thinking.

You use Google's driverless car technology and the perfect information you get from the networked vehicles to create a fluid and ever-evolving transit network. What I'm imagining is that the driverless vehicles don't operate based on a model of individual mobility; they instead operate on a principle of batched mobility.

Let's say for example that there are critical mass of people who want to leave Liberty Village between 8:00am - 8:30am to travel to the Financial District. What they would do is enter this itinerary and then a "station" would get formed somewhere nearby. Users would get notified of the station's location, which would be determined based on proximity to the highest concentration of "riders."

The driverless cars would then get notified and would begin assembling the appropriate number of vehicles at the selected station location. As is the case with conventional forms of public transportation, most people would need to walk to the station. But never that far.

In essence, it would function as a cross between private and public transportation. You would get the economies of scale generated by public transit, with some of the individual conveniences of private transportation.

How does that sound?