Departments of Transportation around the United States have deployed "little white boxes" -- Bluetooth detectors used to monitor traffic speeds and activity. While they're supposedly anonymous, they detect a nearly-unique ID from every car, phone, and PC that passes by. In this presentation, I explore the documentation on these surveillance systems and their capabilities, then build a Bluetooth detector, analyzer, and spoofer with less than $200 of open-source hardware and software. Finally, I turn my own surveillance system on the DOT's and try to detect and map the detectors.