The University of Michigan Library has digitized and made available one million books from its collection.
Here's an excerpt from "One Million Digitized Books":
One million is a big number, but this is just the beginning. Michigan is on track to digitize its entire collection of over 7.5 million bound volumes by early in the next decade. So far we have only glimpsed the kinds of new and innovative uses that can be made of large bodies of digitized books, and it is thrilling to imagine what will be possible when nearly all the holdings of a leading research library are digitized and searchable from any computer in the world.