Discovering the Undiscovered Public Domain
The University of Michigan has begun a project to determine the copyright status of books in it's collection, as described in John Wilkin's blog post.
"At Michigan we're engaged in an activity that I hope will one day seem ordinary and a routine part of library work. Resources from several departments are devoted to determining the copyright status of works typically presumed to be in copyright. For now, we're focusing on US monographic imprints (books, that is) published between 1923 and 1963, but plan to turn our attention to non-US publications in the future. "