Are you an ultra rich person who can't decide between a fancy new yacht, and getting your own little tropical paradise? Perhaps this concept that combines a bit of each in one massive structure could be the solution.
The Tropical Mountain Paradise concept from Island Yacht Design, takes the crazy notion of putting an island right on top of a yacht, complete with a volcano topping it all off. Water flows down from the top of the volcano and into the pool, but to be more realistic, shouldn't that be red hot lava?
Thankfully, this is just some nutty designer's concept. I know really rich people sometimes have pretty questionable taste, but I can't imagine even the most restraint challenged billionaire going for this.