What countries have "green card lottery" systems?

As I understand it, people from all over the world – with the exception of countries that send us more than 50,000 immigrants a year already – can enter a lottery to get a green card to come work in the United States. It’s purely luck of the draw, but once you get that green card, you’re basically free to immigrate here. The only educational requirement is that you have the equivalent of a high school education.

Are there other countries that have a similar lottery system? Many countries have point-based systems, but these tend to weed out everyone except people with graduate degrees or highly needed skills such as computer programmers.

This site (which supports the lottery) says it is unique:

As a person who’s won the Diverty Lottery, and is now a green-card holder, I’ve never heard of anything like it in any other country.

Hmm. Well, if it is unique, I have to give my hats off to the US, because I think it is a great idea that many other countries should consider adopting.