For people interested in ecash / credential tech: Stefan Brands book on his credential / ecash technology is now downloadable in pdf format from credentica's web site: http://www.credentica.com/the_mit_pressbook.php (previously it was only available in hardcopy, and only parts of the content was described in academic papers). also the credentica web site has gone live, lots of content. (credentica is Stefan's company around digital credentials). Adam