Aug. 6, 2008 -- Every August, the mega-yachts descend on the south of France in a swarm of pristine white and fiberglass that glistens above the deep blue waters of the Mediterranean Sea.

By day the yachts, some more than 400 feet long, coast from port to port and marina to marina. The owners, an exclusive club of the world's billionaires, take in local sights, dine at the region's most luxurious restaurants and soak up the sun on what have become their own "floating islands."

"There's an undeniable luxury to these yachts and to know that one person bought it and owns it is pretty remarkable," said Diane Byrne, executive editor of Power & Motoryacht magazine. "It's also a way to enjoy getting away from the craziness of life on land, work and traffic. It doesn't matter whether you're a billionaire or a hard-working Joe, it's a means of escape for them, a way to have a self-sufficient luxury resort all to yourself."

At night, the world's elite come out to play. Dressed to perfection in designer clothing, they shimmy off their boats into the Mediterranean's hottest nightclubs -- Les Caves Du Roy in Saint-Tropez or Cinquante Cinq (Club 55) in Monaco -- for an evening of thumping music and high-class hob-knobbing.

"It's the who's who of… the south of France," said yacht consultant Mark Elliot. "There's the 'boom-boom' rhythm of the music and parties on the docks. Everybody's dressed to the nines -- the beautiful people all coming off of their boats."

For some, the super-sized, ultra-luxurious boats are the main attraction. For yachting insiders, it's all about the far-off, picture-perfect locales where the gigantic yachts drop anchor.

Microsoft co-founder Paul Allen's 414-foot Octopus was launched in 2003. With a permanent 60-man crew, two helicopters, seven boats and a submersible, Octopus is a seaborne estate. For all of its amenities, Octopus requires an estimated $20 million annual budget.

The spirit of good-natured one-upsmanship lives on among the world's yacht-owning billionaires;

Oracle founder Larry Ellison and music bigwig David Geffen co-own the Rising Sun mega yacht, which clocks in at 452 feet. Russian investment tycoon Roman Ambramovich's Eclipse literally overshadows others when it floats into port at a reported 508 feet. The Sheikh of Dubai owns an even larger yacht -- 524 feet long -- that dwarfs those of fellow billionaires.

"It all about prestige," said Vanessa Stuart, administrator for the International Superyacht Society. "If you're the best it's about having the best -- it's all about looks, how it looks to other people. The larger the vessel, the better the man you are or the better the woman you are."

With a mega yacht, Stuart said, "you can have all the toys on board -- your jet ski and all your fancy tenders, your amphibious car, your submarine."

Trinity Yachts Vice President William Smith III said his company has had some unusual requests from customers, from underwater speakers for scuba divers to an inflatable air slide -- (usually found on an airplane) for use as a water slide.

"That's what's great about this business -- it's always changing," Smith said. "You don't have zoning laws; you don't have condo associations you've got to deal with. As long as it's not illegal or un-seaworthy, as long as they're willing to pay, yes, we can do that."

His clientele includes a cast of characters who are "very interesting" and "not the average millionaires," he said.

"Most of our clients are first-generation money and they're fascinating people, just the creativity that they come up with," Smith said. "The owners are at a stage in their life where they want what they want -- the reason they're talking to us is because they haven't found what they want in the existing market."

Making a Grand Entrance

Stuart said the mega yacht world is always changing, with new faces joining the yachting scene every year.

"There's some old money, there's new money," she said. "That's why it's a great industry because if somebody has a great empire and it collapses, someone else comes in, buys it and makes their empire even bigger, then they can decide if they want to have the toy."

This summer, billionaire yacht owners and their ships have crisscrossed the world. Allen's Octopus was in St. Nazaire, Polynesia, the Azores and then France. Ellison's Rising Sun was spotted in Tahiti, St. Tropez and Capri. One of Abramovich's other yachts, Ecstasy, has been to Trieste, Italy, and Croatia.

According to Wall Street Journal wealth columnist Robert Frank, the ideal spot to anchor is a place to dock a tender that can refuel and fill the boat with food provisions from catering companies.

"Probably a nice restaurant as well for the owners to get off and have nice meal even though their private chef is probably the best thing in the world," Frank joked.

The Mediterranean boasts yacht-friendly ports that are known for their natural beauty, history, shopping and ritzy restaurants, Byrne said.

Due to their boats' huge berth, the giant yachts can fuel up and travel almost anywhere, Frank said.

"They can go to the South Pacific, they can go to islands off South America, they can explore parts of the North and South Pole so the advantage is that they can really go anywhere," he said. "But pulling into a place like Monaco or Amalfi or Portofino and being the biggest boat on the block is still very important to these people."

The Mediterranean still reigns as the spot to be seen among the rich and famous, but the popularity of the region comes with a price, Frank said.

"The Mediterranean becomes a giant parking lot for boats and if you try to go to Portofino or Capri or Cannes or Monaco, unless you booked a year ago, you're not going to get a spot even if you have a fairly small boat," Frank said.

He added that the wealthy yacht owners and their guests tend to look down upon anchoring out at sea and riding a luxury yacht tender -- usually a permanently inflated boat -- to the shore.

"Your hair gets messed up when you're on the slip and mistresses complain about not being able to walk onto the dock with the Rolls Royce waiting," Frank joked.

Instead of facing the dearth of docking space in the Mediterranean, yacht owners are traveling to new areas and are inadvertently minting new hotspots for the super-yacht crowd.

"Croatia has become a very popular yacht destination for the Russians, Turkey has become a very popular yacht destination for Europeans and Americans, even Slovenia simply because the Mediterranean has run out of space," Frank said.

Owners are traveling to what used to be considered backwater areas and turning them into yacht destinations, said yacht consultant Mark Elliot.

"The newest, hottest craze has been out to Croatia," Elliot said. "For me, it's 1,000 different anchorages and 100 different islands where you can go to be all by yourself. It's old cities that have been beautifully restored and kept, the water's crystal clear like in the Bahamas."

Elliot said although the shores of Eastern Europe don't have "nightclubbing with the rich and famous," the ports in Croatia allow yacht owners to "get back to a real sense of yachting where you're anchored all by yourself, exploring and getting off the beaten path," he said.

Yacht owners are constantly trying to find the next hot ports, Elliot said. The yacht consultant has seen boats travel up the Amazon River, base out of Alaska for a summer and plan an "around the world" itinerary.

According to Elliot, Saint-Tropez is still the number one summer yacht destination, with Monaco and Portofino in second and third. Spots such as Alaska and North America's eastern seaboard are smaller summertime yacht hubs.

Yacht owners escape the traffic of more popular marinas by sailing to Eastern Europe, Byrne said.

"It's so nice and quiet and is essentially untouched," Byrne said. "It's undeveloped so it kind of has this old world European feel to it -- it's not the hustle and bustle of other ports. They say, 'let's chill and enjoy and have a spot all to ourselves, we don't really want to be in the midst of the action anymore.'"

Smith said that contrary to popular belief, mega yacht owners are "notoriously private" and wish to find a unique luxury escape like Eastern Europe that can be tailored to their needs.

"That's the beauty of these boats," Smith said. "You can send the yacht anywhere in the world and when you need it there's your staff and your stuff in the closet."