Forget all the talk about mortgage foreclosures and a looming recession. Instead, close your eyes and imaging yourself on a boat sailing the Caribbean. Not just any boat, but a megayacht that is two to three times the size of your house.

On board is every luxury you could ever imagine. You can lounge in a Jacuzzi on the top deck while you or your crew barbecue. Prefer something less casual? No problem, a deck or two down is your formal dinning room with a table that seats 12.

Your master suite is large enough to accommodate a king-size bed, walk-in closet and of course your own private bathroom with another Jacuzzi. Fine marble and woodworking adorn every corner of the yacht.

Ready to buy? It will cost you $30 million and up. And don't expect to get your yacht any time soon; there is such demand today for these over-the-top boats that it could take four years before you ever set sail.

That's right, while the U.S. economy slows — if not enters a recession — the demand for these toys for the ultrarich has never been stronger. Several luxury shipyards have seen sales double in the last five years. The rich are not just buying more yachts, but larger and larger ones.

"It's not that significant to them whether we're in recession or not, because they're so wealthy," said Tork Buckley, editor of The Yacht Report, a trade magazine based in London. "The business appears to be recession proof."

Fueling this boom is the emergence of a new class of superwealthy in Eastern Europe, Russia, the Middle East and Asia. And like those before them, these new-money billionaires want all the trappings to prove their wealth.

"It's a must-have accessory, not much different from a watch or a villa or a Bently," Buckley said. "You have to have a yacht."

So you think you want a yacht?

Well, get in line. If you order a superyacht today from one of the top builders, you won't actually get delivery until 2012, Buckley said. It takes about two years to build one and there is a two-year backlog at the shipyards because demand is so high.

This delay is helping some builders outside the traditional shipyards of Holland, Germany and Italy.

American boat builders are seeing new business and countries such as China, which have little experience in yacht building, are starting to enter the market.

A weak dollar is also benefiting American shipbuilders.