I was very upset to hear of the death of Arthur C Clarke yesterday. A true original thinker and someone who has helped open my mind to many things about life, time, space, and the future to name just a few. His books are excellent 'real' science fiction and he prided himself on using only real scientific concepts and theories in his works about space and space travel.
Notable works include 'Childhoods End' which is my own favourite novel of his(and aswell as his book 'The Sentinel' became alot of the basis for his screenplay for 2001: A Space Odyssey) as well as 'The Songs Of Distant Earth', he wrote myriad other novels and short stories that can be found in many anthologies and as stand alone editions.
In my opinion in the field of Sci-fi writing he is only surpassed by Isaac Asimov with whom he was a life long friend and competitor.
So if you haven't read any Arthur C Clarke yet go out and get some...and get some Asimov while you're at it!