I think you're kidding yourself that you're going to get something truly unique. Unless you yourself are going out to the reefs in the more remote parts of the pacific or you are very well connected with someone in the collecting industry, there is little chance that that unique piece reaches you. And if you do by some spectacular twist of fate you were to get such a piece, you had better have the skillset and experience to take care of it - and share frags of it - or in the end you are just destroying that unique item. You can have a superb "unique" tank by patiently hunting down some of the less often seen aquacultured specimens in the hobby. There is no need to pluck from the ocean anymore.