An anonymous reader writes with this report about just how easy it is to disrupt if not entirely kill modern consumer-grade networks -- not just Wi-Fi, but Bluetooth and Zigbee networks, too. Crucial to determining the likelihood of any given kind of attack, though, is how much it would cost the attacker to attempt. The bad news for network owners and users is that it doesn't cost much at all: "According to Mathy Vanhoef, a PhD student at KU Leuven (Belgium), it can easily be done by using a Wi-Fi $15 dongle bought off Amazon, a Raspberry Pi board, and an amplifier that will broaden the range of the attack to some 120 meters."