One of the most interesting presentations at this fantastic conference was given by Eve Gray, of Eve Gray & Associates. Gray was asked to study the publishing strategy of the Human Sciences Research Council (HSRC) in South Africa. This research institution had a traditional strategy of publishing lots of research books, and selling them. Gray convinced them to change their strategyto give away all their research books for free online, and offer a high quality print-on-demand service for anyone who wants the paper version. The result: "the sales turnover of the publishing department has risen by 300%." As she concluded her presentation, "giving away books and lead to an increase in our book sales." There's much much more in her interesting analysis. She has generously offered it for downloading. Here's the press release. Lessig Blog 5/27/05 http://www.lessig.org/blog/archives/eve_gray.pdf
I seem to remember that this was similar to the case with the National Academies Press. Unfortunately, I cannot find or recall a citation at the moment.