"ARE there plug-in hybrid vehicles in America’s future? Such hybrids could travel 10 to 20 additional miles on battery power alone, but until recently automakers have said — more or less unanimously — that it was not practical to add a larger battery pack and plug-in chargers to hybrid vehicles because of the added weight, complexity and cost." The article goes on to discuss potential plug-in hybrids, including the DaimlerChrysler Sprinter prototype, and the potential "green" advantages. Full article Sorry - I didn't realize this is a duplicate of an article posted yesterday.
Plug-in hybrids are soon to come to market. Hybrid vehicles are what are known as bridge technology vehicles anyway until a new fuel source is ratified for mass consumption. Don't expect the US government to give up their petroleum lobby buddies and their deep pockets so that we can use plug-in hybrids or 100% electic vehicles any time soon however.