Isaac Asimov wrote "The Last Question" in one sitting. It appeared in the November 1956 issue of Science Fiction Quarterly and Asimov said it was "by far my favorite story of all those I have written."
It's fun hearing Asimov read it in his energetic Brooklyn accent. But if you listen to Leonard Nimoy's magnificent reading (below), you'll understand why it is usually much better to have a trained actor read a story, instead of the author.
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