This is an awesome example of the use of a bike sensor to collect environmental and health information. Imagine what will be possible when your smart phone can sniff the air, measure temperature, and otherwise sample you and the environment 24/7.
I enjoy reading up on science and one of the web sites I check daily is physorg.com. Today I ran across an article on The Hestia Project an effort by researchers at Arizona State University and Purdue University to create a city-wide CO2 emission visualization system. Pretty impressive they model CO2 fluctuations hour by hour and building by building.