I do think that all of these things are possible. One additional thing is that the government is providing crop circles (steeling from farmers by ruining crops...) to communicate back to these ET's or who-ever is doing this officially real crop circles. HOWEVER -- MOST TO ALL CROP CIRCLES CAN BE RELATED TO A TYPE OF MATHEMATICS; OR FRACTALS. (just by the nature and shape of these crop circles is the evidence I am using.)
For reference in fractals look at:
http://classes.yale.edu/fractals/
Go figure, an ivy league school is hosting fractals; thus something must be true about crop circles and other geometric figures.