Libraries Use DRM to Expire Audiobooks

Some US libraries are using Microsoft Media DRM to automatically return audiobooks checked out of their catalogue. A patron with a valid library card visits a library Web site to borrow a title for, say, three weeks. When the audiobook is due, the patron must renew it or find it automatically returned in a virtual sense: The file still sits on the patron’s computer, but encryption makes it unplayable beyond the borrowing period