Mobile Wifi devices routinely emit probe-req packets giving details of the BSSIDs they have been associated with in the past - the Pineapple device exploits this very feature. Some devices now emit spoofed MAC addresses as part of their tracking preventing. But what if there existed a scalable WiFi scanning monitoring network? Would this enable devices even with obfuscated MACs to be tracked. This presentation describes work-in-progress to built cheap (disposable!) Wifi tracking devices and the infrastructure to support the capture,data-mining, analysis and visualisation of probe-req packet information with a view to understanding the potential threat to privacy it represents.