It’s easy to criticize the rich for extravagant lifestyles, especially at a time when so many are facing financial hardships in a suffering economy. However, what often is overlooked or outright ignored are the philanthropic activities that the richest of the rich are involved with. Supporting causes ranging from higher education to the eradication of terminal diseases, the uber-rich pump billions of dollars into charitable causes around the world. Lear jets and lavish mansions aside, wealthy philanthropist provide a sizable portion of the necessary funds that many worthwhile organizations need to operate. The key for big spenders on this list is the immediate impact of their giving endeavors. Here is a top 10 list that is worth its weight in gold, representing some of the worlds leading philanthropists.

10. Richard Branson

Mr. Branson is a businessman who is familiar with challenges. This is the man who started his own airline. His next step has him taking on one of the direst concerns facing the planet – preserving the environment. To fund his ‘green’ endeavors, such as developing reliable green energy, Richard Branson is donating the profits from some of his business holdings (transportation, which generates an estimated $3 billion). His foundation, Virgin Unite, has even offered a $25 million bounty for any practical solution to cleansing the atmosphere. Seeking to produce results, Mr. Branson continually compensates organizations and individuals who develop solutions to fight global warming.

9. Eli and Edythe Broad

Eli Broad made his fortune in the business area. A well respected businessman, Mr. Broad has focused his acumen on philanthropic activities. He and his wife Edythe manage the Broad Foundations (which features several smaller organizations that focus on specific causes). Interestingly, the Broads endeavor to fund worthwhile causes that no one else does – in fact, this is generally a criteria for their interest in a project. This keen approach has resulted in their foundation assisting in areas where an impact at foundational levels is needed – from doctors performing medical research that’s not quite prepared for government grants to funding training for education administrators. The Broads are also a leader in funding genome research.

8. Warren Buffet

One could easily argue that Mr. Buffet could be much higher on this list when one considers the sheer amount of money that he has provided to charitable causes. A highly successful investor, Mr. Buffet has earned billions. Not taking his success for granted, Mr. Buffet has equally invested billions to various philanthropic causes. Most recently, he has pledged almost $38 billion to assist the Bill and Melinda Gates Foundation (whose work we have listed further down). Additionally, Mr. Buffet awarded each of his 3 children about $1 billion a piece to fund their own, individual philanthropic projects.

7. Thomas Siebel

For this list, impact is the name of the game and Thomas Siebel certainly meets this criteria. When Mr. Siebel became aware of the disastrous effects of methamphetamines on individuals and communities in Montana, he leapt into action. Founding The Meth Project, Mr. Siebel invested a sizable portion of his wealth into a public blitz about the dangers of meth addiction. The Meth Project bought thousands (literally) of ad spots – from billboards to television to get the word out. The results speak for themselves. Montana, once listed as one of the highest states with meth abuse, is now one of the lowest. With such resounding success, Mr. Siebel and The Meth Project are carrying their efforts to other states.

6. William Barron Hilton

The Hilton’s, among the richest of the rich, are certainly known for living a very lavish lifestyle. This image (or perhaps because of it) hasn’t prevented William Hilton from doing his part to help others. To this end, William Hilton has pledged an eye-opening 97% of his personal wealth to the Conrad N. Hilton Foundation. This infusion of cash (estimated to be around $2 billion) will allow the foundation to continue to provide shelter for the homeless, offer vocational training to the disadvantaged, and assist disabled children with obtaining needed educational opportunities. The efforts of the Conrad N. Hilton Foundation are international in scope.

5. George Soros

With as much as $6 billion in total donations to date, George Soros has made an impact in a number areas. Our second hedge fund manager, Mr. Soros knows his way around money. Using this talent for more than just realizing profits for his clients, Mr. Soros has channeled his philanthropic efforts towards many of the social issues in eastern and central Europe. His Open Society Institute has invested funds in such diverse areas ranging from college scholarships to economic relief. With a belief that poverty is often the result of poor government, Mr. Soros also assists heavily in pro-democratic endeavors in many former Soviet bloc nations.

4. Chris and Jamie Cooper-Hohn

This husband and wife duo supports the Children’s Investment Fund Foundation. Mr. Cooper-Hohn is best known for his activities as a hedge fund manager. His shrewd business dealings have earned him a somewhat notorious reputation in the business world. Nevertheless, with the assistance of his wife Jamie; Chris has invested a good deal of his earnings into his charitable foundation. So much so, that the Children’s Foundation boasts of $2.5 billion in assets. Targeting some of the poorest areas of the world (i.e. Africa and the India sub-continent) the Cooper-Hahn’s seek to improve the lives of children. The Children’s Foundation endeavors to have an immediate impact in its endeavors and therefore focuses on areas such as the alleviation of hunger, reproductive health services and the like.

3. Bill and Hillary Clinton

It’s not unusual for former American presidents to be socially active. Such is the case of the next member on our list, former president Bill Clinton. Through his (and wife, Secretary of State Hilary Clinton) William J. Clinton Foundation, the president has been able to channel his own wealth and visibility into a number of worthwhile initiatives. The Clinton Foundation has worked around the world to provide educational opportunities to children (over 10 million), clean drinking water to some of the poorest regions (impacting over 12 million), and working for a cleaner environment (aiding in the reduction of millions of tons of CO2 emissions.

2. Donna and Philip Berber

In terms of impact, there are few that have had as a direct impact as the next entry on our list of Donna and Philip Berber. Philip Berber made millions with his online trading company, CyberCorp and even more once he sold it to Charles Schwab. Apparently, this provided Mr. Berber more time to focus on his charitable activities through his foundation ‘A Glimmer of Hope’. A Glimmer of Hope Foundation focuses on one of the poorest nations of the world: Ethiopia. And the work they have done has had an immediate and needed impact on the lives of millions of people. To date, the work of the Berber’s foundation has resulted in thousands of wells for water being dug, several hundred schools constructed, and much needed microloans granted.

1. Bill and Melinda Gates

The name Microsoft invokes all kinds of emotions in people, and not all of the feelings are good. Nevertheless, whatever one may think about the business practices of Microsoft co-founder Bill Gates, few can fault his philanthropic activities. Teaming with his wife Melinda Gates, the Bill and Melinda Gates Foundation has proved to be a charitable giant. With over $34 billion in assets, the foundation funds initiatives around the world. Ranging from educational grants to medical research – the Bill and Melinda Gates Foundation seeks to assist the people of the world lead improved lives. Mr. and Mrs. Gates donated their entire 2009 dividends from Microsoft stock to their foundation (a whopping $3 billion)!