Individuals, foundations, and corporations across the United States are responding in significant numbers to the global effort to provide relief assistance to the victims of the earthquake-triggered Christmas weekend tsunami that slammed the coastlines of more than a dozen South Asian and East African countries.

On Thursday, according to the Associated Press, the Seattle-based Bill & Melinda Gates Foundation pledged $3 million to the relief efforts, and Microsoft is encouraging its U.S. employees to contribute under an existing program that matches contributions made by employees.

The Washington Post also reports that online fundraising sites are facilitating record donation levels by individuals seeking to respond to the Sunday disaster. As of last Tuesday, 25,000 people had visited RedCross.org to pledge money to aid victims of the tsunami, while just 9,000 people had called the organization's donor hotline. In addition, online retailer Amazon.com has established a link to the Red Cross on its home page and, as of noon Thursday, had recorded more than 75,000 gifts totaling some $4.5 million.

For U.S.-based charitable organizations interested in responding to the disaster, the United States International Grantmaking project, a joint initiative of the Council on Foundations and the European Foundation Centre, is offering special guidance, including copies of Disaster Grantmaking: A Practical Guide for Foundations and Corporations (42 pages, PDF).