I think I finally found the technology behind the crop circles.

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Crop circles, Glowing Orbs, and Scalar Interferometers

Scalar interferometry may explain many unusual phenomena that are being sighted. Two immediately come to mind, the glowing orbs that are being seen in the skies around the world, and the crop circles. Both phenomena could be easily accomplished with the new scalar superweapons. Balls of plasma flying through the sky at phenomenal speeds may well be the "marker beacons" of the scalar weapons. Marker beacons are created for fine tuning the aiming of the devices. Air Force jets were recently sent aloft from Edwards AFB to chase two just glowing orbs. After chasing them a while, the orbs simple vanished. That is to say, the scalar beams creating the orb were turned off.

By feeding a graphic pattern into the aiming software such a plasma ball could be made to trace out that pattern, at the distant interference zone (target zone), making the standing crops fall over, creating a crop circle. Remember there are many modes and effects of these weapons. They are really the engineering of reality itself.>

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The above is part of this link.
It's the closest explanation I've seen, and would explain the phenomena behind some ufo sightings as well:

http://216.247.92.101/pub/bearden/iraq.htm