100 miles per gallon (42 km per liter) ... or even MORE!

''The aim of the AXP is to prime the market to demand cars that use less oil and produce fewer greenhouse-gas emissions.
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Dangle a $10million carrot and watch as engineers deliver both crackpot schemes and genius innovations, any one of which could upend the existing automotive industry.
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The manufacturers say they'd produce fuel-efficient vehicles if people would buy them; consumers say they'd buy these cars if they existed. The principal mission of the AXP is to break this stalemate.
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Founded in 2006 by Steve Fambro and funded in part by storied incubation station Idealab, Aptera plans to introduce its vehicle — a three-wheeled electric two-seater with a 120-mile range and room in back for a surfboard — by year's end. Price tag: $26,000 to $29,000. Its most striking feature is an aerodynamic shape.
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According to the AXP spreadsheet, the Aptera has more than double the efficiency it needs to qualify: It gets 340mpg and spews only 78 grams of greenhouse gases.'' [source]

A "car" that can do 340 mpg!!!! (that's 144 kpl!)