Tetiaroa, French Polynesia
Marlon Brando's private atoll, 30 miles north of Tahiti, now hosts the world's most ambitious eco-resort. 35 villas on a white-sand motu use seawater air-conditioning and coconut-oil energy; a marine research station sits alongside.
Tetiaroa Private Island, French Polynesia
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A 20-minute private plane from Papeete, Tahiti.
From about $2,500 to $12,000 per night, all-inclusive.
Yes, the lagoon hosts manta rays, sharks and turtles.
Yes, it uses seawater air-conditioning and renewable energy.