Hewlett-Packard and Amazon.com are teaming up on a project to turn digital copies of books into paperbacks. They're working with the University of Michigan, which has scanned hundreds of thousands of books from its library into electronic form. Now HP will use its technology to clean up the digital copies — bringing them closer to the original book quality — and Amazon will print and sell them on demand.

Google is experimenting with this model too. The search giant is making some 2 million electronic books available for printing through the Espresso Book Machine, an ATM-like contraption that reportedly spits out paperbacks in less than 5 minutes.

Interestingly, many of the University of Michigan's library books were scanned by Google (though the university digitized some of the books itself). HP says it's only working with public domain, out-of-copyright titles from the Michigan library — thereby steering clear of some the issues that have dogged Google's massive book-scanning project.

(Amazon and others raised objections to Google's proposed legal settlement with author and publisher groups over the book project. The settlement is currently being revised on court supervision.)

Can turning digitized copies of old books into paperbacks be a big business?

"It has the potential to be significant," said Andrew Bolwell, director of new business initiatives for HP.

"I don't expect any of these books to sell Harry Potter volumes," Bolwell said. But he said, "No matter what the book, there's always demand out there. All of these books have a niche market."

Bolwell said HP will provide cleaned up versions of the scanned books to Amazon, which will offer them for sale on its website. When people order one of the books, Amazon's BookSurge on-demand publishing service will print a copy, sell and mail it. Amazon, HP and the University of Michigan will split the proceeds, though Bolwell declined to break down who gets what.

Applewood Books, a seller of American historical books, will also offer select titles from the University of Michigan. Another service, Lightning Source, will do the printing for Applewood.

The HP announcement builds on a deal Amazon made with the University of Michigan back in July. I've asked Amazon for comment.

Update: Amazon spokesman Drew Herdener confirmed that BookSurge is printing public domain work from the University of Michigan, but didn't elaborate on HP's role.

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