If it isn’t captured in video or photographs, it didn’t happen.
Sousveillance is a terms coined by Steve Mann to describe the recording of an activity from the perspective of a participant in the activity, typically by way of small portable or wearable recording devices that often stream continuous live video to the Internet.
Simple technology like a camera, smart phone with social media, video, or audio capabilities can be used for this purpose. A more sophisticated approach includes items like this pair of glasses that sends real-time video to the Internet.
For more information see, Using Sousveillance to Defend the Commons or download Steven Mann’s, Sousveillance: Inventing and Using WearableComputing Devices for Data Collection inSurveillance Environments (PDF)