He was one of the greatest people of our time.  More than just an author.  More than a great scientist.  More than an engineer, physicist, humanitarian, advisor, prophet, philosopher, and more.  He helped define the world we live in from the positive side.  He helped define who I am today through his stories.  He had his hands in most of the great information technologies we enjoy today.  We all owe him more than we can know.  And now he is gone.  Goodbye, we will miss you.

From the BBC:  Writer Arthur C Clarke dies at 90