We have ~this the other way around: the Dutch American Friendship Treaty allows US citizens to come to Holland and start a business (freelancer is Okay). You need 4.5K capital, sustained, and it renews every 2 years.
That is very interesting, I didn't know about it. I feel like the capital requirement still means that it isn't for "labor" though. For instance, can people using that program get jobs? I wish my country, and others, would lower these sorts of barriers and let people go wherever they can be successful and happy.
I would love it if the US could reciprocate :(
http://en.wikipedia.org/wiki/DAFT_%28treaty%29