CAPHIS (open access - free registration)
A US site. "The purpose of the CAPHIS Top 100 List is to provide CAPHIS members and other librarians with a resource to use in their daily practice and teaching. Secondly, it is our contribution to the Medical Library Association so that the headquarters staff can refer individuals to a list of quality health web sites. Our goal is to have a limited number of resources that meet the quality criteria for currency, credibility, content, audience, etc."