In light of last week's events in Haiti, the need for legitimate, emergency-based responses is huge. Global Giving steps up to the plate by "offering an online marketplace that connects you to the causes and countries you care about. You select the projects you want to support, make a tax-deductible contribution, and get regular updates so you can see your impact." Whether you select to give to a certain type of project or a project in a certain place, you choose where you want to make a difference. You can even post your own projects in need of funding.