Mobissimo

If you're bored with those above the ground five star hotels, why not try the Poseidon? "When/if built, the hotel will be a world's first permanent one-atmosphere sea floor structure and the world's first true undersea resort. Guests will enjoy 5 star luxury accommodations, all with stunning views of the underwater world."

Unlike the Jules Undersea Lodge - the only undersea hotel now in existence, located off the coast of Key Largo, Fla. - guests at the Poseidon won't need to put on a wet suit and dive to their accommodations. They also won't need to worry about changing pressure levels since the accommodations will be maintained at above-surface pressure. Instead, they can glide to their $1,500-a-night underwater abodes by escalator.

Make your reservations now. Ask for the Octopus' Garden Room. In the shade.