At $4.00/gal for fuel one could drive 100,000 miles and still not break even with regards to the extra cost of the hybrid feature. How many batteries will have been replaced during this period and at what cost? What other energy resources will be required (electricity/natural gas, diesel) to dispose of the spent batteries and at what cost? What about the energry and materials to make the batteries in the first place? Can these batteries just be thrown in the land fills along with the other garbage?