I just had a thought with regards to your CO2 example.
What if companies were required to clean up their waste (in this case CO2)
by purchasing/creating forested land that can convert their equivalent CO2
output into clean air? Granted it would be more expensive than just
polluting, but it would be an interesting way to handle industrial
pollutants. This is already done to some extent in the timber industry
through reforestation. A system like this could be applied to a great many
industries and would go a long way towards protecting "public goods" by
enforcing a zero-sum usage policy.
I already see some obvious flaws in this, but it could be a step in the
right direction in some industries. Instead of purchasing the "right" to
pollute from the government, many people would be better off if industry
returned public goods in the condition they obtained them in.