Animals

• The Humane Society of the United States - seeks a humane and sustainable world for all animals—a world that will also benefit people.
• VegFund.org - acquainting the general public with the joys of a plant based diet.
• The World Wildlife Fund - protects natural areas and wild populations of plants and animals, including endangered species.

Bicycling

• Bike Forest
• Bikes Belong - works to put more people on bicycles more often.  Bikes Belong funds projects that leverage federal funding and build momentum for bicycling in U.S. communities.
• The League of American Bicyclists
• Outspoken Bicycles

Earth/Environment

• EarthSave International - Healthy People, Healthy Planet.
• Friends of the Congaree Swamp

Education

• Math in Motion by Barbara Pearl - "In her Math in Motion workshops and books, Barbara has created a wonderfully delightful and practical guide to using origami manipulatives that makes math come alive in the hands and minds of all children." Steven Leinwand, President of the National Council of Supervisors of Mathematics.

Public Health

• America on the Move -  a national nonprofit organization whose mission is to improve health and quality of life by promoting healthful eating and active living among society, communities, families and individuals.

Technology

• Tests – Tests.com is the largest directory of tests with 50,000+ test listings organized by category: academic, career, environmental, medical, personality and more.
• Todays Tech Now – cool technology reviews from Colin Detweiler, a young entreprenuer.