Though hand-carried versions won't fire at a million rounds per minute--no soldier would want to reload every three milliseconds--vehicle-mounted systems could. Art Schatz, the senior vice president of operations in Washington, D.C., says that if larger barrels were clustered on the back of a Humvee or in a helicopter, the result would be a powerful "area-denial" weapon. The system can be adjusted to meet various needs. "We're not talking about always firing at a million rounds per minute," Schatz says. "But if you've got one of these mounted in an aircraft and have a rocket-propelled grenade coming at you, you can in an instant have 200 little bullets intercepting it." Moreover, Metal Storm could fire nonlethal rounds such as rubber bullets--for, say, crowd dispersal. The system's key drawback: The guns require electrical power, making them yet another gadget soldiers will need to keep supplied with batteries.