A lot of people must be considering alternative transportation because of high gas price.
Bikes, motor bikes or small electric cars can be available. But they aren't safe when the cars are passing by at 40 or 60 mph. Then how about reducing speed limits to 25 or 30 mph? It is essential to safely promote bikes and other vulnerable transportation means.
There is a way where we can reduce speed limits without compromising the time needed to travel: make cities compact! Assume your town is 20% more compact than what it is now. You can reduce driving speed from 60mph to 48mph, and you still can get to the same place with same amount of travel time. Or, if the key services are effectively aligned, you could reduce your travel time even more with slower speed.
Compact city is a relatively new idea for sustainable urban development that focuses on
1) Central area revitalization
2) High-density development
3) Mixed-use development
4) Services and facilities: hospitals, parks, schools, leisure and fun
There is much more about compact cities, here are some links.
I strongly believe that making motor vehicles eco-conscious can never happen on its own. It has to come hand in hand with community planning and development.
University of Reading, UK: Compact city
Developing a compact city and a network region: Sweden
The compact city and the environment: a review: Netherlands
photo from: http://www.transport.gov.za/projects/msa/msareport/msarpt_fig82.gif