Poseidon Undersea Resort, Fiji

The Poseidon Undersea Resort is putting a positive spin on "sleeping with the fishes," by providing guests with the lap of luxury 40 feet beneath the waves. Nestled amongst a 5,000-acre Fijian lagoon, the resort is the world's first of its kind. An elevator provides access to the 24 suites and one apartment on the bottom of the ocean floor. Plus, 70 percent of each room is made of four-inch acrylic, allowing unparalleled views of the surrounding sea life.

You may need to admire this one from afar, however: It costs a staggering $15,000 per person for two people traveling together. Rates are based on a package price that includes round-trip transport to and from Nadi/Suva, four nights in a beach or overwater villa, two nights in an underwater suite, diving onboard a luxury liner submarine, an initiation to piloting a three-passenger mini-sub, scuba diving and snorkeling, walks on the lagoon floor, wine tasting classes, access to the resort spa (some treatments cost extra), gourmet meals and drinks, a professionally-produced photo album, and lectures and activities.