There's good news for those tired of waiting for global warming to turn the country into an equatorial archipelago. Endless summers on private island paradises are no longer only for the shipwrecked or reclusive.

"Isolation has ceased to be a form of deprivation," says Cheyenne Morrison of Coldwell Banker Morrison's Private Islands. "In the modern world of mass travel, mobile phones, faxes and e-mail, isolation is the scarcest commodity."

But it'll cost you. Vatu Vara, the most expensive island on this year's list, has an asking price of $75 million, and comes with miles of white-sand beaches, palm groves, an aquamarine lagoon, limestone cliffs and surrounding waters filled with sailfish and black marlin. To the extent neighbors exist on an island chain, Mel Gibson lives just down the way, 20 miles east on Mago Island.

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But sometimes, just as with local housing markets, there are compelling reasons to rent.

"Man cannot live by one island alone," says John Greer, president of Unusual Villa & Island Rentals. "Why have only one island, when you can have them all?"

Finnish fashion designer Peter Nygard's private island in the Bahamas, called Nygard Cay, rents for $35,000 per day and has played host to Oprah Winfrey, Robert DeNiro and Sean Connery. The Mayan-inspired compound boasts an aquarium, three-screen movie theater, tennis court, volleyball court and 48-foot fishing boat.

Worried about the slow pace of island living? The legendary Atlantis casino on Paradise Island is only 20 minutes away.

Why buy?

The benefits of a private island are obvious, especially for high rollers hounded by photographers. They offer complete privacy, beautiful scenery and weather, and pristine beaches free from others' footprints.

But good islands are hard to find. In the best locations, such as the Caribbean or South Pacific, many are protected nature reserves or have been sold off to resort developers. Some countries, such as the Philippines or Fiji, have restrictive laws regarding foreign ownership of islands.

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To further limit supply, inhabitable islands don't come on the market very often. Marlon Brando bought his Tetiaroa atoll in 1965 after filming Mutiny on the Bounty and held onto it until his death in 2004. Prices, as a result, are in the stratosphere.

This year, for example, Forbes.com's list of the most expensive islands bottoms out at $25 million for Coakley Cay in the Bahamas. Though we spoke with brokers and scoured listings for the properties on our list, there are likely other properties that are being quietly sold at comparable rates or higher.

And, in most cases, the listing price doesn't include necessities of island-living such as food, water and shelter, as most islands are completely untouched. No megamansions here. For example, clocking in at No. 2 is Ronde Island, a 2,000-acre tropical diver's paradise off the coast of Grenada. For $70 million, one gets a completely undeveloped isle more than 2,000 miles away from the nearest Home Depot, a tough slog even for those with a Gulfstream V.

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"A lot of people think it's a thrilling thing to be on an island, which it is," says Greer, "But people forget that at 11 at night, you can't go down to the 7-Eleven and buy cigarettes."

A starter island, likely a remote desert-isle fixer-upper, filled with mosquitoes and in need of utilities and a residence, might run about $200,000. And even though many islands on the market are larger than some of the world's smallest countries, such as Monaco or Vatican City, buying an island does not make you president-for-life of your own nation. Rather, you'll be a guest of the host nation.

Because all islands fall under the control of sovereign nations, a buyer would have to bribe a corrupt government to cede sovereignty and then be recognized by a few world powers. Not surprisingly, asking prices are generally cheaper in volatile countries, such as Sri Lanka or Indonesia, but there are obvious risks.

"In secondary markets, where there isn't a consistent rule of law, your investment is dependant on political stability," says Farhad Vladi of Vladi Private Islands. "In Fiji, they just had a coup d'etat and no one knows what [new president] Frank Bainimarama is going to do when it comes to foreign investment. He could make it difficult to buy and develop islands."

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If you're able to navigate through all the financial, logistical and political challenges of finding an island, make sure to study weather patterns. Beach erosion, tidal waves, hurricanes and monsoons can quickly leave newbie beachcombers marooned in a bad situation in a country they don't know much about.

"You will no doubt be seduced by the surroundings," says Morrison. "But you have to ensure you tread carefully because there are traps and pitfalls at every stage of the property buying game, facts that do not change just because you change country."

Why rent?

Renting an island removes any such risks. With full-service staffs, team of chefs, private planes and boat fleets at the ready, renters live like royalty. Richard Branson's Necker Island, which once hosted Princess Diana, has a staff member to guest ratio close to 2-1, and Isla de sa Ferradur, in Spain, has an underground cave spa featuring whirlpools, a Turkish bath, sauna, beauty salon and massage facilities--perfect for recuperating after a night spent on nearby Ibiza.

Of all the trade-offs between renting and buying, one thing is for certain. In either case you can take a long walk on the beach and have no one bother you.