The Math Forum
Combined archive and portal to web resources, educational issues, help forums, mailing lists, and teaching materials. http://mathforum.org/
Cancer Research Foundation of America (CRFA)
Dedicated to cancer prevention through scientific research and education. CRFA is a national non-profit organization focusing on preventable cancers such as colon, breast, cervix, prostate, lung and skin through education and by funding grants and fellowships. http://www.preventcancer.org/