This story changed the way I saw writing with the way it portrays it as a tool that can be used or misused just like any other.
Honorable mentions to:
"Microcosmic God" and "If all men were brothers would you let one marry your sister?" by Ted Sturgeon
"Bordered in Black" and "Neutron Star" by Larry Niven
"Blood Music" by Greg Bear
"Special Delivery" by George O. Smith
"The Gold at the Starbow's End" by Fredrick Pohl
Forster is better known for writing period romances like A Room with a View. The Machine Stops, written in 1909, deals with issues of isolation and alienation that come with advances in communication technology, and it sort of kind of predicts the internet.