An anonymous reader writes to mention an Engadget post on an incredibly powerful wifi scanner. The 'Janus Project', as it is called, can sniff 300 networks simultaneously. It stores and encrypts the data as it receives it, for later use. From the article: "In addition, the Janus Project has an instant off switch, which requires a USB key that has a 2000-bit passkey and a separate password to regain access. What's under the hood? Williams packed an Ubuntu Linux machine running on a 1.5GHz VIA C7 processor with an Acer 17-inch screen into that snazzy little rugged yellow box. Oh, and the closed case is waterproof too, in case you need to transport Janus Project on a whitewater raft to your next hacking hotspot. We don't doubt someone will." The post leads to a tgdaily article, which offers more details.