Facebook founder Zuckerberg (Mark Zuckerberg) and another 16 American billionaires have become the latest batch of philanthropists to respond to the call of Microsoft founder Gates and "Oracle" Buffett, pledging to donate most of their fortunes. The 26-year-old Zuckerberg said that people like him, who achieve success at a young age, do not need to wait until the end of their careers to do good deeds.