Using something of "the wisdom of crowds," this relatively new site is a serious real-time disease outbreak surveillance tool available to all. Wondering whether there is an outbreak on your part of the globe or in your state? This is a nice and well-tested resource, and one that continuous to improve.
As described in the latest issue of the Public Library of Science (PLoS) Medicine (see sidebar for link), "the goal of HealthMap is to deliver real-time intelligence on a broad range of emerging infectious diseases for a diverse audience, from public health officials to international travelers." And, it provides "an integrated and contextualized view of global health information."