Non-Useful Non-Lethal Weapons

The Active Denial System or 'pain ray,' which works well -- as long as you let it warm up for 16 hours. (Dept. of Defense)

The Pentagon's Mobility Denial System, basically slippery foam, lets a van spin its wheels while going nowhere. Unfortunately, it also requires a steady supply of water. (Dept. of Defense)

The FN-303 non-lethal projectile launcher in use by Marines in Afghanistan in 2007. The GAO report found it fell apart easily, and its compressed-air canister were hard to keep supplied. (Dept. of Defense)

A truck-mounted laser dazzler. It temporarily blinds unruly mobs -- but can permanently blind the GIs operating it or standing nearby. (ArmorCorp LLC)

The Taser X26, which can zap people by launching wired projectiles 35 feet -- but can't be used around flammable materials or in the rain. (TASER International)