Gasoline prices have been falling in the last few weeks, but – for most U.S. drivers – they remain painfully high. With regular unleaded costing a national average of $3.78 per gallon Tuesday, and more than $4 a gallon in six states and the District of Columbia, prices are more than $1 higher than they were a year ago. "When you fill your tank and you're putting $60, $70 or $80 into your vehicle at a shot, you start to wonder if there's an alternative to this madness," said Scott Doggett, associate editor for Edmunds.com.