My wife totaled her car last summer, so we shopped around. I considered a new $24,000 Prius, but ended up buying a used 2006 Hyundai Elantra for $11,000 out the door. We keep our cars until they die, so the numbers work like this: If she gets EPA mileage and drives the EPA average miles/year, we can drive the Elantra for 14 years on the price difference between it and the Prius. We can drive it another dozen years for the price of the two battery replacements the Prius will need over the next 20 years. So that's 26 years of free driving before the Prius's mileage advantage starts to factor into the equation.