I am not sure if this is right but I think it is because it is such a fascinated idea when it was first thought of and as of now. It hasn't been invented and no one knows how to. I guess that us humans are inquisitive individuals and what we cannot achieve are probably what we want to value the most. But I assume that you are talking about the movie?
Well, apart from the above ideas, the movie is valued because, i think, it was a well made film at that time. if I have remembered the film correctly (does it have a woman name Rowena or likewise?), it also sends out an important message, it didacts issues that we are facing now.