At the University of California researchers are working to exploit a massive distributed sensors network: the cell phones network! Take a look at the video they have created to show their vision to exploit and leverage on the multiple sensors present in our cellphones.
And then take a look at their website on Urban sensing to understand the variety of information that can be gathered and constructed based on data picked up by the billion of cell phones around the world.
There are benefits for the individual, starting from his health care and for the Society as a whole.
This is Digital Life and Digital Lives at its best! And it is also about pervasive computing as we have never seen before!