Already in use are such things as infrared cameras with built-in brains that capture license plate images and match them in milliseconds to police records of vehicles of interest to the authorities.

Such license plate recognition systems, fixed and mobile, already are stopping criminals in cars in New York City, Washington D.C. and 23 states, according to Mark Windover, president of Remington ELSAG Law Enforcement Systems, which is marketing its product to 250 U.S. police agencies.

"Seventy percent of all criminal activity can be tied to a vehicle," he said. "Had to get there, had to go home."

Remington ELSAG says its algorithms -- which turn images into data in the blink of an eye -- could guard airports, military bases and other federal facilities as well as crack down on the drug trade, robberies and other crime hinging on stolen cars.

In other surveillance developments, the Department of Homeland Security, or DHS, is defending a plan to make broader use of eyes in the sky that, until now, have mostly fed military and scientific needs.

"The use of geospatial information from military intelligence satellites may turn out to be a valuable tool in protecting the homeland," Democrats on the House of Representatives Homeland Security Committee wrote to Homeland Security Secretary Michael Chertoff this month.

But they voiced privacy and civil liberties concerns about the scheduled October 1 launch of the National Applications Office, a clearing house for expanded output of imagery to police, border security and other law-enforcement outfits.

"We are so concerned that, as the department's authorizing committee, we are calling for a moratorium on the program until the many constitutional, legal and organizational questions it raises are answered," Chairman Bennie Thompson of Mississippi and colleagues wrote on September 6.

SATELLITES, TINY AERIAL VEHICLES

DigitalGlobe, a potential beneficiary of stepped-up demand for such products, launched a satellite this week that can daily collect up to 750,000 square kilometers of imagery able to pick out suitcase-sized objects. The WorldView-1 satellite is part of a U.S. program, dubbed NextView, designed to give government customers priority access.

Many of the gizmos under development will be pitched first and foremost to the Pentagon, which is increasingly trying to keep tabs on foes in urban and other hard-to-monitor settings.

Lockheed Martin Corp (LMT.N: Quote, Profile, Research), the Pentagon's No. 1 supplier by contract value, is working on a keychain-sized, remote-controlled aerial vehicle designed to collect and transmit data with military and homeland security uses.

Resembling the seed of a silver maple tree, the single-winged device would pack a tiny two-stage rocket thruster along with telemetry, communications, navigation, imaging sensors and a power source.

The nano air vehicle, or NAV, is designed to carry interchangeable payload modules -- the size of an aspirin tablet. It could be used for chemical and biological detection or finding a "needle in a haystack," according to Ned Allen, chief scientist at Lockheed's fabled Skunk Works research arm.

Released in organized swarms to fly low over a disaster area, the NAV sensors could detect human body heat and signs of breathing, Allen said.

"The NAV swarm can pinpoint the location of survivors, send the data back to the first responders and help concentrate rescue operations where they are most likely to be successful," he said in an e-mail interview.

Meanwhile, Boeing Co (BA.N: Quote, Profile, Research) is leading the technology segment of a multiyear plan to secure U.S. borders that includes database and intelligence analysis systems.

Projected by U.S. Customs and Border Protection officials to cost as much as $8.8 billion over the next six years, the system also features ground-based and tower-mounted sensors, cameras and radar plus high-speed communications, command and control equipment and devices that detect tunnels.

Airport screening is another area that could be transformed within 10 years, using scanning wizardry to pinpoint a suspected security threat through biometrics -- based on one or more physical or behavioral traits.

"We can read fingerprints from about five meters .... all 10 prints," said Bruce Walker, vice president of homeland security for Northrop Grumman Corp (NOC.N: Quote, Profile, Research). "We can also do an iris scan at the same distance."

(Additional reporting by Andrea Shalal-Esa)