It sounds like science fiction, but it's real--a heat ray that can zap a mob and force people to flee without inflicting permanent injury. On Jan. 24 the U.S. military unveiled its Active Denial System, right, which shoots a beam of electromagnetic radiation calibrated to cause an intense burning sensation (similar to touching a hot lightbulb) but no long-term damage. Unlike traditional brute-force tools of dispersal--such as batons and rubber bullets, which can maim or even kill--a new wave of high-tech crowd-control devices promises to keep the peace without causing casualties.
PHASR
The Personnel Halting and Stimulation Response uses laser beams...