Living in the sticks as I do, I've visited my mates farm a few times. His mates had created some crop circles using a plank of wood. It excited a bit of local interest apparently. We gave it a go and its ridiculously easy.
Moral of the story: Its unlikely to be lay-lines, UFO's, weird energy things - and much more likely to be a few drunk blokes and a plank of wood. Not as exciting really. Sorry.