... The recently announced program allows individuals to request the digitization of any public domain book listed in the Open Library ...
If a public domain work in Open Library’s catalog hasn’t yet been scanned, the item record will display a “Scan This Book” button. Click it, and a librarian at [Boston Public Library] will be prompted to grab the item off of the shelf and queue it up for digitization. In three to five days, you’ll get an email telling you that the digital copy of your chosen book is ready to go. Of course, in the spirit of openness, the digital copy isn’t yours alone—copies will also be made available through the Open Library item page and through Open Library’s parent venture, the Internet Archive. For more info, and a list of public domain books along with each item's scanning status, check out openlibrary.org/bpl.
The open access movement:
Putting peer-reviewed scientific and scholarly literature
on the internet. Making it available free of charge and
free of most copyright and licensing restrictions.
Removing the barriers to serious research.
I recommend the OA tracking project (OATP) as the best way to stay on top of new OA developments. You can read the OATP feed on a blog-like web page or subscribe to it by RSS, email, or Twitter. You can also help build the feed by tagging new developments you encounter.