Microsoft's software wizard and the world's second-richest man is having the most productive midlife crisis in history. His focus on creating, promoting and distributing vaccines is having a massive impact on global health. Gates' goal is to eliminate infectious disease as a major cause of death in his lifetime. He may succeed.
2011 Highlight: Malaria vaccine he backed recently passed a key clinical trial. The vaccine has the potential to save millions of lives.
At the top of the list are:
1. President Barack Obama
2. Vladimir Putin, Prime Minister of Russia
3. Hu Jintao, Chinese President
4. Angela Merkel, German Chancellor
5. Bill Gates
6. Abdullah bin Abdul Aziz al Saud, King of Saudi Arabia