What would aliens actually look like?

Speculating about what aliens look like has kept children, film producers and scientists amused for decades. If they exist, will extra terrestrials turn out to look similar to us, or might they take a form beyond our wildest imaginings?

The answer to this question really depends on how we think evolution works at the deepest level.  And as we approach the year 2020 the search is getting more and more interesting.

So send in your ideas of how you imagine aliens would look like.