Can't deny that Tolkien is the father of all modern fantasy, but I much prefer the Discworld, since it has both sweeping fantasy laugh-out-loud quirkiness, my cup of tea is a strange tasting one to others.
I also quite enjoy the Science-fiction works of one Arthur C. Clarke, who is probably best remembered for tales such as 2001: A Space Odyssey (he both wrote the novelization and co-wrote the screenplay for the 1968 classic film with Stanley Kubrick), Childhood's End, Rendezvous With Rama, and The Fountains of Paradise, among others.