Crop Circle Connector seems to think so:

Modern crop pictures often concern themselves with comets and their strange behaviours. Could the recent outburst of Comet 17P Holmes have been shown in English crop pictures from the summer of 2007, or from any other summer over the past few years? Upon careful study, I found that few if any crop pictures from the years 2007, 2006, 2004 or 2003 could possibly be interpreted retrospectively in terms of an “exploding comet”. Yet literally dozens of crop pictures from the year 2005 could be so interpreted, in a fairly clear and obvious fashion.

It seems a bit far-fetched to me, but see what you think.

Then read Kathryn’s take on the upcoming transit of Comet Holmes over the fixed star Algol:

The coming Jupiter/Pluto conjunction in Sagittarius, the sign of Faith, coincides with one of the dates that Comet Holmes is expected to reach Algol, Dec 11th 2007. This could indeed speak of calamity and strife arising from despotic leaders in the name of religion or even global/galactic horrors. However, this stupendous comet and these aspects could also herald the birth of a new way of thinking and being. An illumination of spiritual consciousness that is leading us into a wonderful new era under the guidance of some very wise men or women.