In June 2006, Bill Gates announced he was stepping down from his full-time role at Microsoft and shifting his focus to the Bill and Melinda Gates Foundation. When the world's richest entrepreneur decides to take a step in the nonprofit direction, he may be onto something.

In the last decade, a generation of social entrepreneurs has become increasingly visible by creating self-sustaining businesses. Social entrepreneurs are similar to regular entrepreneurs with one main difference--their gains aren't measured in financial profit, but by the impact they have on society... Read more.

Source: Entrepreneur.com