There are many sustainable technologies designers can utilize these days to make a project more Earth- and people-friendly, but smog-eating cement isn't the most talked-about - until now. The City of Chicago is pioneering the use of a revolutionary type of cement that is capable of eradicating the air around it of pollution, potentially reducing the levels of certain common pollutants by 20 - 70% depending on local conditions and the amount of exposed surface area.