Just donated $20 to UNICEF for Haiti relief efforts after reading Hari's blogpost. It's not a lot of money but I always believe if everyone contributes a little, the world will be a better place.
So I encourage you to go to Hari's blog and donate through the links he listed. For one thing, Haiti is the poorest country in the Western Hemisphere and its citizens have long been suffering from poverty before the earthquake. Just imagine that for a moment. And add the earthquake.
Here is an American's account for the earthquake, it's an sobering experience.
And learn about Haiti the country on Wiki.