"Ready Player One" by Ernest Cline. It was fun to read for at least three reasons: extreme resourcefulness of the main character, an imaginary world that is both future and retro, and learning new obscure details about classic games. There were mostly no dull moments in an otherwise very linear story.
I also found the typographical easter egg hidden in the text, that was fun :) Don't really want to spend time playing Atari 2600 games though.
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