I searched the forums and found only a couple of glancing mentions, buried in the middle of other threads, of the National Academies Press, which periodically puts out some of its titles as freebies for download. These are mostly (all?) in .pdf format.I'm not going to try to list even the current ones. Although they are sometimes really timely (e.g. some books and reports NAP put out about energy a while back), most of the titles tend to be pretty esoteric. For example, some current freebies include:* Challenges and Opportunities for Education About Dual Use Issues in the Life Sciences* The Science of Adolescent Risk-Taking: Workshop Report* New Worlds, New Horizons in Astronomy and AstrophysicsAnd the NAP website can be a little cloogey to navigate.But, if you're looking for some cutting-edge, well-refereed (I was on a National Academies committee, and the peer review process was long and detailed) books or book-length reports on topics which sometimes are of current interest, I think their stuff is worth checking out. Disclaimer: although I served on one NA committee, I don't work for NAP, nor am I pitching our committee's report...which is not free anyway :)There is a "freebies" webpage as part of their site: http://notes.nap.edu/category/free-from-nap/And you can also sign up for their e-mail updates, which include info on new freebies, here:http://www.nap.edu/updates/index.htmlAnyway, for all of you nerds, errrrrrr, us nerds, out there...this is, IMO, a website worth checking out from time to time.