On a project with NDI, we built a site to show polling data from the recent election in Afghanistan. We put this on a map and overlaid
it with other data like security threat levels, which helped show where fraud
took place: http://afghanistanelectiondata.org/data.
Two other examples of open data in use are two projects we worked on with the New America Foundation. One shows data on all public
school districts in the US with 65 different data indicators: http://febp.newamerica.net/. The other
is a data browser that maps and charts health indicators in all 50 states with
data over the past 30 years: http://statehealth.newamerica.net/.