Carlo Zapponi has created a wonderful visualization of the world's migration patterns as of 2010 using HTML5 technology. The project, called PeopleMovin and found at http://peoplemov.in, has lots of information about migration in general as well as the country-specific numbers. For instance, about 3.15% of the world's population lives outside of their countries, and the United States is the most popular migrant destination. Refugees and asylum-seekers make up about 8% of all international migrants, and the majority of those (65%) come from North Africa and the Middle East.
This website is set up fairly intuitively, with two long columns stretching down the page, split into sections representing countries. If you click on a bar on the left-hand side, information will come up concerning the number of people who left the country and the country they went to. Here's the information for the United States:
The lines connect to the corresponding countries on the right-hand bar, and the thickness of the lines indicates the number of people who moved.
If you click on a bar on the right-hand side, you'll get information for all the people who moved into that particular country, and their countries of origin. Again, the thickness of the line indicates the number of people. Here's the United States:
It's really a beautiful interface, and it's very easy to lose some time playing around with it.