The trouble with living in a cube of glass in the sky is that you have to return to earth eventually.
But even at sea level, you don't have to feel that you've come down in the world.
Inspired by the tastes of a younger generation of tycoons, ultra-high-end yacht makers are trying to re-create the style and comfort of multimillion-dollar big-city condos: the open floor plans, the indoor-outdoor spaces, the glass walls and the sleek lines.
One yacht -- a $45 million Veloce from Benetti -- even has a "beach club": The back of the vessel folds down to create a sunbathing deck open to the water, with a grill and a bar attached.
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