I find the varied references to UFO like experiences in Ayahuasca visions pretty fascinating e.g.
In spite of the frequency with which Pablo depicts spaceships, he is sparsein his commentary about them. Pablo says that these vehicles may take manyshapes, are able to attain infinite speed, and can travel underwater or underthe earth. The beings travelling in them are like spirits, having bodies moresubtle than ours, appearing and disappearing at will. They belong to advancedextraterrestrial civilizations that live in perfect harmony.
check out Pablos artwork(http://www.ayahuascavisions.com/index.html ), internet seems a bit lax on discussing this element
an article chewing the cud on topic^^
have quite a few friends who all have different experiences, My only reccall with aliens has been whilst lucid dreaming
I reckon humanity as a whole is far too conditioned in sense of "me/I" identity and all the stories that come along with that, by and large there's too much restless churning of the mind for us to recognise these more "advanced" subtler forms of life that probably keep a beady eye on us - we're way too distanced from the present moment to grok em I reckon :)!
I enjoy the work of this collective http://temporarytemples.co.uk/ lots of great effort in documenting crop circles - they publish a photobook of all the ones of the year they have photographed (I don't think there are any other such annual publications)
if you're interested I'd recommend giving this book a read http://temporarytemples.co.uk/product/crooked-soley-a-crop-circle-revelation
it makes the "crop circles as people DIYing" it look too heavy handed a theory (some probably are but all of them? year in year out for the entertainment of a tiny fringe of interested people?) - regardless the circles/craft/visions/experiences etc are an enigma of our times, they keep life exciting! they encourage us into relationship with the unknown and mysterious, they make us think.