Develop a technology to make the air that we breath cleaner. I believe that there are already some technologies that prevent pollution to go on the atmosphere ( in the cars exhaustors, for instance), but we could make something to put on cars, buses, houses, offices, and streets, that separate the clean air from pollution, retaining the pollution and giving the clean air back to the atmosphere. Maybe we could turn this retained pollution in something useful, like we are already doing with waste. I´m not sure if this is possible or desirable, nor if somebody already has made it, but I always think Environment in terms of Organization of natural elements. The pollution is the result of a "bad organization". So, let´s re-organize the Nature. Of course we should not pollute, but considering that we won´t stop polluting instantly, it might be a helpful tool.