"Gang members in Chicago who fire off a few rounds at their rivals [could] find cops on the scene in minutes, thanks to new gunshot-detection devices being installed in 80 locations around the city before the end of the year," Wired News reports.

The devices, mounted on telephone poles in specific neighborhoods, listen for the distinctive sound of a gunshot and immediately alert a police dispatcher when one is detected. A video camera in the device allows the dispatcher to keep an eye on the scene until officers arrive.

The system is similar to those being used to decrease gunshot-related injuries and deaths in a half dozen other cities in the United States, including Redwood City, California; Glendale, Arizona; and Charleston, South Carolina.

Here's how the systems work: Police mount the detection devices, which include microphones and sound-analysis hardware, on telephone poles and other locations in neighborhoods where gunfire is a problem. The devices are connected to a control center where dispatchers wait to receive alerts via their computers.

Chicago authorities have been getting increasingly worked up about using distributed technology to keep tabs on their less-than-friendly residents. In September, Mayor Daley announced a proposal to network together 2,000 surveillance cameras around the city.

Chicago's gunshot detectors sound a whole lot like Darpa's "Boomerang," sniper-finder system, which G.I.s have been mounting on their Humvees since early in the year. More info on the project's next stage --designed to fight off RPG attacks, as well -- is here.