This document discusses how new technologies like crowdsourcing, social networks, and citizen science can enhance biosurveillance and public health through big data. It provides examples like Ushahidi and Google Flu Trends that track diseases. Mobile games and heat maps using machine learning can gather health data. Platforms like InSTEDD and data journalism sites are proliferating. Future challenges include scaling coordinated data sharing for public good while ensuring accuracy, privacy, and governance over this new "data commons". Organizing dynamic health surveillance will require more flexible collaboration beyond traditional control models.