Amazon has announced plans to offer buyers of printed books a copy of the text in digital form for free or at a discounted price.
Its Matchbook scheme will apply retroactively to any title bought from the store since it opened in 1995.
At present the offer is only being publicised on the firm's US website.
Amazon said the programme would launch in October and would include more than 10,000 titles. Publishers involved include Harper Collins and Houghton Mifflin Harcourt.
The retailer said it was now urging other authors and publishers to enrol.
The only problem that I see with it is that checking the box that gives Amazon permission to bundle your print and digital books is that the robots see this as a different file, and so the book is taken off the market for the same time that it takes to republish an updated version. But no doubt this will be sorted out in due course.