The military’s efforts span an enormous technological gamut, from sponge-tipped rounds, rubber-pellet-filled grenades, vehicle-arresting barriers and slippery foams to laser dazzlers—which are used to disorient and temporarily blind—and tasers. And that’s just a sampling of the technology already in service or expected to be within a few years.
On the counter-personnel front, the technology is only marginally more tame. Nonlethal, after all, does not mean nonviolent. Although information here remains scarce—and the directorate won’t share details—the pulsed-energy projectile rivals the Active Denial System pain beam in its sci-fi promise. The weapon will fire a pulsed (in brief shotlike bursts) deuterium-fluoride laser that will produce an ionized plasma on whatever surface it hits. That in turn will cause both pain and a kinetic shock, and could literally knock people off their feet.
Another counter-personnel system, the veiling-glare laser, is designed to produce fluorescence in the human eye, inducing a whiteout effect, blinding individuals for brief periods. Acoustic devices that produce low-frequency, incapacitating sound are also being investigated as counter-personnel weapons.
Then there are the malodorants, the chemical brews that mimic revolting smells and can disperse attackers and crowds. Malodorants may send people packing a lot faster than the most expensive laser weapon imaginable.
More here.