Common sense
An amazing number of things like this fall prey to simple "man on the cracker barrel" questions, like "how did someone manage to set up a camera where a crop circle was going to appear?"
Off Topic » in reply to excellent link - should be bookmarked
An amazing number of things like this fall prey to simple "man on the cracker barrel" questions, like "how did someone manage to set up a camera where a crop circle was going to appear?"