I often harp on he need to institute a revenue neutral carbon tax (cut payroll taxes). That said, there are other measures that I think are also important in terms of providing incentives to develop cleaner energy sources and maximize conservation.
1. Cities should institute congestion taxes. From a fiscal standpoint for cities it makes sense. I think this could have two effects- cities would broaden their tax base in the literal sense that there is an added revenue source (even if you use it to offset a reduction in say income, property, or sales taxes levied at the local level) and you would likely broaden the tax base as I think you would encourage folks that are on the bubble economcally, the marginal case, to ditch the suburbs for the city. Obviously, by raising the cost of commuting by car public transportation becomes more palatable. To a smaller extent I expect congestion tax to shift some income from the burbs to the city and thus to shift some housing inward as well, thereby, reducing the footprint of development.
2. Horsepower taxes. I understand people want to surround themselves with a lotta steel and still have a badass ride, that said, there are some externalities associated. If you have a carbon tax a horsepower tax would be largely unnecessary, but it may be easier to pass one of these politically.