Health, Health and Health Links

Hardin Meta Directory of Internet Health Sources has pointers to the most complete and frequently cited lists in each medical discipline.
http://www.arcade.uiowa.edu/hardin-www/md.html
Health Canada - Division of Aging and Seniors
http://www.hwc.ca/datahpsb/seniors/index.htm
Medical Matrix
http://www.slackinc.com/matrix/