We humans yearn for new, interesting, attractive species - for exciting aliens that look like ourselves, who are (so to speak) our relatives but who have to offer something special, too. We want to be astonished, but not scared by a very special characteristic of extraterrestrial beings. Fortunately, we leave it to the media world, that often adapt the appearance of the fictional aliens in dependence of their danger levels, to spread fear regarding the aliens. But how could real intelligent aliens look like and what is purely fictional? What do the experts say to the probable appearances of the aliens?