A man who was, from a production point of view, rarely afraid to push the boundries of what people said could be done. He may well be the butt of many jokes for the the unrealistic movement of his puppets (which did get better as technology improved), but he did advance both TV and film model effects.
Plus he made some damn fine stories.
RIP, and I'll just leave this here for posterity..
http://www.youtube.com/watch?v=BfIAKj3Gl1E
Edit, and this :
http://www.youtube.com/watch?v=lMEuEF9-UbU