From The Future at Work podcast, a short video interview with Deborah Estrin about participatory sensing. This is essentially about people collectively compiling data, for instance using their cell phones (since that is today’s most ubiquitous and easy-to-use data collection device). Estrin describes an application of participatory sensing, What’s Invasive, where people locate invasive plants using their iPhone or Android. This could be, for instance, in a national parks, where both employees and trekkers would be able to snap geo-coded photos (through GPS, although the photos do not strictly need to be geo-coded; they can be annotated later through a website). There’s a strong overlap with citizen science here.
Estrin also briefly describes an interesting application which traces your own path through a city over days, weeks or years and mashes up the spatial information with data on air quality. Air quality varies in different locations in a city and over time, but with this application you can get a pretty good approximation of the pollution you tend to get exposed to. This may prompt a change in your regular bike route, for instance. (Bonus link: The Beijing air quality Twitter feed)