Green philanthropy got a major shot in the arm in September when Virgin CEO Richard Branson announced that he was giving $3 billion-the anticipated profits from Virgin Group's airline and rail businesses-to fund renewable energy research and development by non-profit organizations and for-profit businesses during the next 10 years. It was perhaps the largest amount of cash that any single person had devoted to the renewable energy cause in one fell swoop.

Of course, Branson's pledge isn't that purely altruistic form of giving without expecting anything in return. Sir Richard stands to benefit financially from his largesse, and it will additionally act as a kind of offset for the emissions caused by Virgin's enterprises. Yet that amount of seed money will go a long way in spurring development, innovation, and progress of renewable energy.

Branson's announcement got the lion's share of the attention at the Clinton Global Initiative, an event organized by the Clinton Foundation that also garnered other important commitments: Former World Bank President James D. Wolfensohn launched a $1 billion investment fund for renewable energy sources (which may not exactly qualify as philanthropy, but is still commendable). LIME investor Steve Case announced that The Case Foundation would be giving a $5 million donation to PlayPumps, an organization that installs filtration systems throughout Africa, enabling communities access to clean water by using the power generated by children playing on merry-go-rounds. Barbra Streisand and Rupert Murdoch gave $1 million and $500,000, respectively, to the Clinton Climate Change Initiative, which helps cities and urban areas reduce greenhouse gas emissions and become more energy efficient.

Fortunately for the rest of us, giving it away is getting easier by the day. Nowadays, you don't even need to donate directly to charity. With the Bono-spearheaded Product Red brand, part of your purchase of certain products goes to The Global Fund, which fights AIDS, malaria, and tuberculosis in Africa.

But if you want to be a little more targeted in your giving, there are different ways of giving green to green. Here are our top causes to give to-and you can donate to all of them online:

• The Organic Consumers Association, an organic- and local-foods advocacy organization, acts as a sustainable foods watchdog and protects organic standards from being diluted by big business and government.

 

 

• The Rainforest Alliance encourages sustainable farming practices and indigenous economic development in ecologically sensitive regions throughout the world.

 

 

• The Sierra Club, the bastion of environmentalism, was formed in 1892 by renowned naturalist John Muir and likeminded outdoors-o-philes with an intent to "make the mountains glad" through conservation campaigns, political action activities, and organized outings into the natural world.

 

 

• Heifer International helps families and communities to attain a degree of self sufficiency by giving them livestock that provide subsistence and food; it also teaches them sustainable farming techniques as well as business skills-a worthwhile endeavor.

 

 

• The Nature Conservancy acts as a steward for ecosystems through conservation programs, habitat restoration projects, and land purchase agreements, preventing development and preserving the integrity of natural landscapes.

 

 

• The Asian Classics Input Project, by finding and translating millennia-old Tibetan and Sanskrit texts, is ensuring that the profound spiritual wisdom of Tibetan Buddhism and other Eastern traditions will survive for modern audiences and future generations.

 

 

• The American Botanical Council nurtures understanding of herbal medicine by compiling information about different treatments and documenting scientific research into the field; the group offers an online database of herbal therapies.

 

 

• The Permaculture Credit Union, a banking cooperative for the ecologically minded, provides loans to members to buy hybrid cars, build yurts, and install solar panels.

Even if you can't afford to make a monetary contribution, you can make a lifestyle pledge or a commitment of a more pragmatic sort that commits you to earth-friendly action, like volunteering, making your own home more energy-efficient, or using less water. Sites such as the Clinton Global Initiative provide forums where visitors make pledges about making a change for the better. Altruism comes in many forms, and all of it helps us move closer to our own Elysium.