Volunteer-built map of Beijing flooding...
"Authorities and Internet users have made maps of Beijing roads and areas that were flooded during Saturday's downpour as the municipality braces for more heavy rain today." (www.chinadaily.com.cn)
"Beijing’s Internet users banded together last week to solve a time-sensitive problem—mapping the hardest hit areas of the city in the wake of major flooding and warning other residents to steer clear of hard-hit areas" (techpresident.com)
"Citizens’ joint crowdmapping effort not only materialized prior to the government-sanctioned map, ...it also proved more accurate and intuitive." (www.crowdsourcing.org)