Clinical Reference
The Best of the Best in supersites for the clinician. A one stop shop for all that one might need in knowledge based information.
OpenMD Directory
University of Iowa choose these sites through the use of the google search engine. Google ranks sites in order of the frequency other sites have chosen these individual listings as links.
Martindale's Health Science Guide
A directory that contains subcategorized links to textbooks and tutorials, science articles and medical cases databases.
Healio
Free Registration required, but well worth the effort.