My first thought when I read the tittle, oh it may about how to support legalization of bitcoin in some countries. But lol, it's totally different compares to what Op mentioned above, to buy an island? You should change the title of your thread man.
There will be few people that might be interested, depends on the location of the island, idea to share it, how much it costs and for what purpose/benefits to collect bitcoin from many people to buy an island?
I won't invest obviously, the island may not so important for me in the future, except if the idea is really really good.