Carl Sagan's enthusiasm and optimism about our future in space is highly infectious. I remember watching parts of the series when I was younger and enjoying it. I recently found it in my Dad's collection and just had to watch it again, and it was even more beautiful than I remember it, because I was able to understand so much more.
He puts it in terms that anyone can understand, and more importantly, he puts it in terms that everyone can get excited by. Hearing him talk so enthusiastically about the cosmos is truly inspiring. I hope humanity reaches the potential he saw in us. He was a truly great man, and I'll always remember him. May he rest in peace.