A couple of years ago I met Jason Epstein in passing and he excitedly described his new project: a machine to print On Demand Books. The plan is finally bearing fruit: the Espresso Book Machine was demonstrated at the New York Public Library on Wednesday. Three of the machines are out in the wild, and I suspect many more will appear if the prototypes live up to the hype.

The idea of books on demand is a little eerie but eminently efficient. Publishers and booksellers waste millions of dollars, tons of fuel and forests of paper shipping, returning and trashing unsold books every year. And if a machine like this isn't too expensive to run, it could revolutionize education in less accessible or wealthy parts of the world. The real question is whether such a machine might do to bookstores what Netflix has done to video rental stores. The Espresso machine can only print paperbacks, so for now I think Barnes and Noble is safe. And even if the shelves are replaced with digital browsing displays one day, many customers will still want to enjoy their purchases with an overpriced latte and pastry. The social spaces of book-reading have yet to be destroyed by Amazon.com or the blogosphere, so I think they'll survive a new kind of espresso machine.

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