NASA Tech Briefs is a monthly magazine that summarizes technologies developed through NASA research and their commercial applications. Free of charge, the magazine's Web site has much of the information that is published in print, while also offering an easy-to-navigate interface. The Tech Brief Library is an archive that dates back four years in twelve different categories, ranging from mechanics to software. The Technical Support Packages have even more detailed information in downloadable Adobe Acrobat (.pdf) files. If you want a subscription to the magazine or electronic newsletter, there is a link to the fee-based subscription services.