Surveillance psychiatry is an emerging practice which seeks to predict and prevent mental illness across a broad population by using algorithms and big data. A new generation of digital systems for policing normal are currently in beta and will soon enable authorities to control all modes of social deviance and protest. Electronic health records, data mining social networks, and even algorithmically classifying video surveillance will significantly amplify this approach. Researchers are claiming they can diagnose depression based on the color and saturation of photos in your Instagram feed - and predict manic episodes based on your Facebook status updates. Corporations and governments are salivating at the prospect of identifying vulnerability and dissent. Although they will carefully use the language of suicide and violence prevention, these lines are not so clear. When algorithms are scrutinizing our tweets to determine who is crazy, it will become increasingly difficult to avoid a diagnosis. But there is hope. In this millennium, a new wave of mad resistance has emerged - the Mad Underground, a thriving network of mental health activists who are developing innovative strategies for resisting psychiatric domination and creating new models of community driven emotional support. By listening to their voices and understanding their visions, we can diffuse the menacing time bomb of big data surveillance psychiatry before it explodes, putting the depths of our emotions in the realm of public consumption and subjecting us to new forms of oppression.