World Vision is a trusted Christian relief and development organization that is hard at work in the aftermath of the Tsunami tragedy. They've set up a special phone number for donations: 1-888-562-4453.
Due to the volume of traffic, their site has been slow. But you can make a donation to help the victims, or sponsor a child in Sri Lanka or India. Here's more on what World Vision is doing.
Also, hats off to Amazon.com for setting up an easy way to donate to the Red Cross. The money is pouring in. (HT: Instapundit)