OA to grey literature. Paola De Castro and Sandra Salinetti, Quality of Grey Literature in the Open Access Era: Privilege and Responsibility, Publishing Research Quality, Spring 2004. Not even an abstract is free online to non-subscribers, at least so far. The rest of the Spring 2004 issue is dedicated to grey literature. (Thanks to Charles W. Bailey, Jr.) (PS: Although I've used deep links to the article and issue, they probably won't work for you. You'll have to register at the site and then hunt for the article and issue all over again. Transaction Publishers isn't trying to make it easy.) [Open Access News]
most people know that i have a strange interest in grey literature, i encourage others to have it to. it is one of the best ways to increase understanding.