David Henderson quotes  Robert Guest's new book Borderless Economics:
When people try to think of ways to ease global poverty, they seldom mention migration. They tend to instead think of things like microcredit. There is nothing wrong with microcredit (the lending of small sums of money to poor entrepreneurs). It has lifted many people out of poverty, which is why Mohammed Yunus, whose Grameen Bank pioneered this approach in Bangladesh, won the Nobel Peace Prize in 2006. Yet, as Mr. Pritchett points out, the average gain from a lifetime of microcredit in Bangladesh is about the same as the gain from eight weeks working in the United States. After doing a quick calculation of the total benefit that Grameen Bank confers on its clients, he asks, mischievously: “If I get 3,000 Bangladeshi workers into the US, do I get the Nobel Peace Prize?
Indeed. I give to Kiva.org  regularly and I'm very happy to support the good work they do. Nevertheless, information like this makes me think about how much more effective my money might be. That, and how much richer the world would be if we were more open to foreign people working in our countries.
So: what charity can I give to that smuggles poor people into rich countries?