Snipers have long been one of the more dreaded foes in combat. Now there is a "sniper detector" system arriving in Iraq that is cheap, portable and effective enough that it might make a difference. The Boomerang system consists of a small sensor that is mounted on an aluminum pole rigged to the back of a hummer or truck. A wire runs from the pole to a PDA size display mounted on the dashboard or windshield. If anyone fires a rifle nearby, the sensor picks up the shockwaves and soundwaves and instantly calculates the distance and direction of the fire. The display also has a speaker, which barks out a warning message along the lines of "incoming, seven o'clock" (which is standard military lingo indicating direction of enemy fire.) The display then shows the location of the fire relative to the vehicle. This bit of information is important in urban combat, because all those buildings cause the sound of a single shot to echo and confuse everyone as to where it's coming from. Moreover, the Iraqis are, in general, lousy shots, and will often fire several times before they hit anything. Or, the smarter Iraqis will get off several shots and then move to another location before they can be spotted. The really dumb Iraqis let off a blast of automatic fire, which is much easier to spot. Boomerang enables U.S. troops to quickly swing their weapons in the right direction and return fire. This may hit the enemy who just fired, will most likely spoil his aim, and will probably cause him to stop firing and get out of there. Some fifty Boomerang systems were given to army and marine units willing to use them in Iraq. The system took only two months to develop by a Massachusetts company, BBN Technologies Inc. DARPA provided the money needed to fund that effort and the marines provided the live fire testing in their training area at Quantico last December. Each Boomerang system costs $10,000, but that is expected to come down to about $3,000 if it works in Iraq. It might not work in actual combat situations. For example, Iraqi urban areas are noisy places, and the additional noise, from many sources, might make Boomerang less effective, perhaps to the point where it's not much help at all. If Boomerang does work, the developers can improve the technology to make it more accurate and plan to install networked Boomerang systems throughout hostile urban areas, using wireless data transmission to provide a constant record of gunfire, and where it's coming from.