The Chilbolton 'Arecibo message', made in August 2001, is one of the most controversial and interesting of all crop circles. It introduces a new element of binary code with a discrete message into a 30-year pattern of geometric designs with non-specific messages. Paul Vigay's article written after he personally visited the formation site and posted on his Crop Circle Research web site is reproduced below.

The Chilbolton (2001) formations are consistent with the pattern of slow escalation in crop circle and extraterrestrial messages. Crop circle appearances were nearly unnoticed for about 20 years, from around 1971 until 1991. During this initial 20 years, simple circles and lines in formations were uncannily similar to the designs that Carl Jung wrote about in his 1957 treatise, Flying Saucers: A Modern Myth Of Things Seen In The Sky. Jung noted that the symbolism associated with UFO reports [and later seen in crop circles] were the same symbols found at the deepest levels of the psyche. When traditionalists concluded that the similarities between symbols in UFO reports and the psyche must mean that UFO's are projections of the psyche, Jung responded that until we can explain how projections of the psyche register on radar at speeds of 3,000 miles an hour we must look for other explanations.

source/read more: http://www.timestar.org/ccchilbolton.htm