A recently declassified US Army report on the biological effects of non-lethal weapons reveals outlandish plans for "ray gun" devices, which would cause artificial fevers or beam voices into people's heads.
The report titled "Bioeffects Of Selected Nonlethal Weapons" was released under the US Freedom of Information Act and is available on this website (pdf). The DoD has confirmed to New Scientist that it released the documents, which detail five different "maturing non-lethal technologies" using microwaves, lasers and sound.
Released by US Army Intelligence and Security Command at Fort Meade, Maryland, US, the 1998 report gives an overview of what was then the state of the art in directed energy weapons for crowd control and other applications.
Some of the technologies are conceptual, such as an electromagnetic pulse that causes a seizure like those experienced by people with epilepsy. Other ideas, like a microwave gun to "beam" words directly into people's ears, have been tested. It is claimed that the so-called "Frey Effect" – using close-range microwaves to produce audible sounds in a person's ears – has been used to project the spoken numbers 1 to 10 across a lab to volunteers'. - ns