I don't think these special vehicles like TFA car will achieve any real commercial success. Most people want a safe, comfortable and practical car. And you most certainly don't want anybody to laugh at you while riding it...

No, I believe the future (until fuel cells are available) lays in hybrids, like the Toyota Prius, even though they're still not completely environmental friendly - fuel consumption is not better than most diesel powered cars. But battery powered only cars have their problems as well, darn expensive, well you have to plan your trips carefully, batteries have a limited life span and probably more important batteries are not environmental friendly.

Here is an interesting hybrid from Saab, running on 100% ethanol and batteries. It's a good looking convertible, and runs 0-100 km/h in just 6.9 seconds, not very bad from a fossil fuel-free car. Only problem is that 1) you can't buy the car yet 2) you can't buy 100% ethanol (and producing large amounts of ethanol is also a problem).