We've been spending a lot of time in used books stores lately, poring over vintage and new alike. When I saw this idea it made me think we should be looking for some vintage favorites of my son so that we can turn the covers into frames.
Having a cluster of 3 or 5 book frames would be even better. Another idea would be to frame classic family photos in hardcover books from the same era. Lauren Elise, guest posting at papernstitch, runs through the whole tutorial.