Last weekend, I saw an excellent, if mildly depressing, movie called The Devil Came on Horseback, about the genocide in Darfur. What saves the move from being a total downer is that it tells the story of a former U.S. Marine captain named Brian Steidle, who did a tour of duty as a monitor for the African Union, and became an activist on behalf of the people of Darfur. His passion and commitment are inspiring.

So, too, is the work of other activists who are working hard to prevent the genocide. Some bring pressure on investment firms that will not commit to divesting companies that do business with Sudan (notably Fidelity Investment). Others are pushing U.S. companies to do what they can to bring economic pressure on Sudan and its most important ally, China, in connection with next summer’s Olympics in Beijing.

Did you know that the actress Mia Farrow has been to Darfur seven times? I didn’t either until I wrote today’s CNNMoney.com column about Dream for Darfur, a group she chairs, and its efforts to get corporate sponsors of the 2008 Beijing Olympics to speak out against the genocide.

Here’s how it begins:

Good citizens speak out when they see injustice. Can good corporate citizens be expected to do the same?

That’s the uncomfortable question being raised by a human rights group called Dream for Darfur, which is asking sponsors of the 2008 Olympics in Beijing to voice their opposition to China’s support for the government of Sudan. The Sudanese government has been accused of waging a genocide against its own citizens in Darfur.

You can read the rest here.