Wi-Fi Jammer
A device called Cyborg Unplugged can be configured to prevent any Wi-Fi connection:
Oliver notes on the product’s website that its so-called “All Out Mode”—which prevents surveillance devices from connecting to any Wi-Fi network in the area—is likely illegal, and he advises against its use. Nevertheless, we can imagine activists slipping these little devices into public areas and wreaking a bit of havoc.
Chelloveck • September 9, 2014 2:44 PM
It’s not a jammer per se. It downloads a list of unwanted MAC addresses (presumably wildcarded by OUI) and denies them access to the network. Non-blocked devices still have network access. Furthermore, if I’m reading this correctly, when an unwanted device is connected to a different access point this unit can spoof a message forcing the device to disconnect.
IMHO this device isn’t very useful. It’s fine if you want to block access to your own network, but if that’s the case you’re really going to be better off whitelisting the few approved MACs instead of blacklisting the bad. If you’re disconnecting people from other networks you’re much more of a “glasshole” than anyone wearing Google Glass or streaming video from their phone.