Maybe it's already been written but I would like to read a sci-fi novel where humanity realizes that our atmosphere is at risk and begins a race to capture it. The end result being that the planet's atmosphere is completely sucked up in to massive containers of liquid air. These are controlled by a few entities around the world, i.e. those who were most successful at liquefying air when it was free. Liquid air then becomes the main commodity about which all commerce is based. Who you get your air from determines your social status and vulnerability.