Financial markets notwithstanding, most of us were happy to see gas prices fall. It has certainly helped to put a little extra breathing room in our household budgets, even though we suspect it could lead to increased use of fossil fuels. On the other hand, it could open the door for some new initiatives to help control emissions, such as a carbon tax, or a fee and rebate plan that would tax the production of fossil fuels and give the proceeds out to all Americans.Perhaps this would be a good time to take a closer look at what that gallon of gasoline actually costs us, when all the impacts are considered.