During an hour of Midday last week, David Sandalow, the Brookings Institution fellow and author of Freedom From Oil, was bullish on plug-in electric vehicles as a key element of the nation's energy future. Imagine infinite mpg -- no gasoline at all -- for most of your near-home driving. There's been a lot of hype about the Chevrolet Volt, an electric plug-in with long-range power. (It can go 40 miles before a recharge; the vast majority of American commutes are less than that. The Volt will switch to gas or E85 after 40 miles, allowing the lithium-ion battery to recharge.) Earlier this month, GM's board reportedly approved a mass-production rollout of the Volt in 2010. It would be revolutionary if we could get this right -- and make it affordable to the masses. John McCain's $300 million to the techie who comes up with a long-long-range battery for cars was about the smartest thing he's done or said in a while.