In order to promote their ebook reader, Microsoft is giving away free ebooks for a limited time. Just install the new Microsoft Reader and start downloading ebooks.
Here's a clip from their web site. "Summer 2003 is here! What better way to celebrate than to relax with a good book? To help you make the most of this special time of year, Microsoft is pleased to offer a compelling introduction to the world of eBooks. Never read a Microsoft Reader eBook before? Now’s your chance! Through this special offer, you can download best-selling titles from a wide range of notable authors . . . for FREE! This offer will run from July through November, 2003."