Mark Zuckerberg is an American entrepreneur who co-founded the social networking site Facebook. He is the youngest billionaire in the world. Mark has recently taken his place among the most charitable people in the world who are also atheist (Bill Gates & Warren Buffett). In 2013 Zuckerberg was the most charitable person in America... done completely without the aid of religious belief!!
He listed "atheist" for his religious views on Facebook.
Source: WSJ by Vauhini Vara, The Wall Street Journal, November 28, 2007 (Accessed March 30, 2008).