sort of related, but there is an open database over at WiGLE.net which has WiFi and Bluetooth MAC addresses stored with timestamps and GPS coordinates so, if y

sort of related, but there is an open database over at WiGLE.net which has WiFi and Bluetooth MAC addresses stored with timestamps and GPS coordinates so, if you were within range of a device scanning wireless bands at a certain time in a certain place, light forensic analysis of your phone, wearables, car, etc. could place you in the vicinity of a crime with up to dozens of times the resolution of mobile network tracking you bought the burner phone, the burner SIM card, disposed of them by ..burning, but drat! that blasted Fitbit got you fingered and that's just one example of open involuntary surveillance. scanners can be small, cheap and housed anywhere with minimal electrical power. in urban areas it would be trivial to track permanently and store indefinitely someone's minute-by-minute position, especially in conjunction with known CCTV blindspots