These 3 wheeled cars are built for performance, but if they had a smaller engine and improved areodynamics they would have really good fuel economy. They weight around 1,000 pounds so that helps alot.

http://www.go-t-rex.com/

http://www.vwvortex.com/artman/publish/volkswagen_news/article_1647.shtml

http://www.sub3wheeler.com/index.php

http://www.vigillante.com/vigillante1.htm

http://www.rqriley.com/tri-mag.html

(you can order plans on this page. I bet you can find them for free if you look on the internet for a while)

http://www.arielatom.com/ariel/site.php

a very light 4 wheeler)

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2008 EPA adjusted:
http://www.gassavers.org/gaslog/sig.php?id=249
http://www.gassavers.org/gaslog/sig.php?id=414
Distance traveled by bicycle in 2007= 1,830ish miles
Average commute speed=25mph (yes, that's in a car)

Those are really cool.

I sort of want to build my own car now

Although it is still in development (they are presently constructing the prototype), the Aptera diesel-electric hybrid by Accelerated Composites (http://www.acceleratedcomposites.com/) looks promising with its 330 mpg projected mileage and its cd of 0.055.

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http://www.cleanmpg.com/garage/images/3209.png]
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