Crop circles are actually advanced binary codes, more advanced than anything humans have. Either that or they are markers for interplanetary time-travelers. This, according to a UC trained chemist named Dr. Horace Drew, who presented his thesis at a recent conference in Australia.
http://www.coasttocoastam.com/article/scientist-claims-to-have-decoded-crop-circles/
Examples of translations the scientist gave from crop circles included simple concepts, “Much pain but still time. Believe. There is good out there,” or “beware the bearers of false gifts and their broken promises.” “Also, friends don’t let friends vote Democrat” and ‘Rough day – lets get drunk”. Its suggested the aliens are more-or-less talking down to us humans, and trying to communicate basic ideas we could have in common.