nice idea, but the comon ground is very small.
take CO2 scrubbers ... a complete waste of time, money IMHO, but no doubt well worth it if you want to reduce CO2.
take hybrids (please, take them for a long drive off a short pier) ... of course they get 60 mpg 'cause they obtain a significant amount of their energy from the grid ... possibly worthwhile if you're trying to reduce consumption (waste of time IMHO, though i like the idea of regenerative brakes).
that leaves improving efficiency, which i think is a good thing, but i'm willing to bet that others will think it's not enough, that consumption and emission will carry on regardless (as i expect they will).
then there's carbon trading ... what a way to scam money from folks. i tell ya, someone's getting rich out of this and it ain't me (i'm not smart enough).
off soapbox ...