Peter Suber has published "Unanimous Faculty Votes" in the latest SPARC Open Access Newsletter.
Here's an excerpt:
One year ago today there were 12 known cases of unanimous faculty votes for institutional OA policies.
http://www.earlham.edu/~peters/fos/newsletter/06-02-09.htm#marylandToday there are more than twice as many. Here's a quick review and update.