Call Elio the anti-alternative car: Quirky, but bound and determined to be mainstream rather than niche. That's why this three-wheel, two-seat, one-door car was at the Village at Corte Madera shopping mall last Friday--to show everyday people what their second car could look like.

That's right, second car. Elio harbors no illusions about this slender automobile's capabilities. Built to accommodate a single person and a non-claustrophobic friend, along with a few belongings, it's simply too small on its own to do more than run a few modest errands.

Here's the trunk, for instance, which was just carved out of the shell with this prototype stage.

"We're finding out more about where this vehicle fits," said Jerome Vassallo, Elio's vice president of sales. No pun intended, I'm sure, on how easily the 160.5-inch long car fits within the profile of many traditional cars; rather, he meant how the Elio fits into your personal transport needs. "It's in addition to, not instead of, a regular car," Vassallo continued.

With a base price of just $6800, you'd think some young-singles would buy it just because it's cheap. Elio even offers financing.

So far, however, that hasn't been the case. Most of the 25,166 preorders as of July 21, Vassallo admitted, have been placed by white males aged 49-60 years. "It's typical of any startup--they're the people with the excess income," he explained. "We're dipping into the 30-year-olds a little, but we haven't gone viral."

Even a second car needs some basic attributes for people to use it, however, and Elio's still working on that. In addition to the new trunk, which is big enough to stash a couple of standard-size backpacks, Prototype 4--the successor to Prototype 3, seen at CES in January--is designed to meet NHTSA and IIHS safety guidelines, with crumple zones, three airbags, and a steel frame.

It's not crash-tested yet, because the car's still in prototype, but something this small certainly brings up questions. In fact, the one 30-something guy I saw looking at the Elio asked about ABS and other safety features.

Other improvements focus on adding a few more miles to the Elio's already-generous fuel economy. Dark plastic skirts now cover the front and rear wheels to minimize air disturbances while driving.

The headlamps were also integrated into the hood to improve airflow. In Prototype 3, they protruded from the side of the car like reptilian eyeballs.

You're going to need more than integrated headlamps to improve the Elio's drive performance. According to the specs, the 3-cylinder, 55-horsepower engine offers 55 lb.-ft. of torque, giving the car an anemic acceleration of 0-60 rate in 9.6 seconds.

That's part of the price of green, but here's the bonus: The car gets 84 mpg on the highway. With an 8-gallon tank, that gives you a range of 672 miles. Pollution is low, too: According to Elio, you'd have to drive the car 20,000 miles per year to produce the same amount of greenhouse gases as the typical cow.

The engine, of course, has yet to be produced, but here's a prototype that was shown next to the car.

To know me is to customize me

Part of Elio's charm may end up being the customization possibilities. "We're going to make the car, but we're encouraging third parties to make options for it," Vassallo said. None of those options are available yet, but Vassallo listed examples such as bicycle or wheelchair racks, all of which could fit along the doorless right side. I'm sure these items would wreak havoc with the carefully designed aerodynamics, as all racks do, but the point is to expand the car beyond simple people-carrying (which is basically all it can do on its own) and tailor it to your specific needs.

Elio has some busy months ahead. The engine could be in production by the end of the year, and the car itself is due to ship in September of 2015.

And that coveted 30-something buyer? Not surprisingly, the Friday-morning crowd skewed older and retired. Most likely the weekend brought in younger adults. But with many of them toting children, friends, or even shopping bags that couldn't fit into this car, the Elio still has some convincing to do.