MSNBC:

A little over a year after Bill Gates and Warren Buffett began hatching a plan over dinner to persuade America’s wealthiest people to give most of their fortunes to charity, more than three-dozen individuals and families have agreed to take part, campaign organizers announced Wednesday.

[…]

The pledge is a moral commitment to give, not a legal contract. It does not involve pooling money or supporting one cause or organization. It’s up to each person who signs the pledge how to divvy up their wealth.

Say what you will about Bill Gates and Microsoft, but this is completely awesome. This is the kind of hero the 21st century needs.