[Paid4This]

You can do just about any pattern, if Michagander's pic is the one from Naperville, it even looks like the ones in the movie posters. Copycat from the movie or out and out publicity stunt for the movie.

[Dengar01]

Michigander's pic is the actual pic of the crop circle. My first thought was the closeness in proximity to the huge movie theater. So hoax seems to be the best answer. However, the local news has given a large amount of coverage to this story.