Any mere millionaire can own a supercar these days. But how many can own a supercar yacht?
In what could set a record for both speed and excess, a few supercar owners and companies have started building boats modeled after supercars like Ferraris and Lamborghinis.
These aren't just wild concept drawings. These are actual boats that can cost four or five times as much as the supercars that inspired them.
"These are guys who just love their cars and want a boat to match," said Tim Gallagher, sales and marketing chief at Marine Technology, which has built multiple supercar-yachts. "It's different."
Marine Technology's latest creation is the floating Aventador. Gallagher said that a few years ago, he had a boat built to look like his Mercedes. He liked it so much that when he got a bright yellow Lamborghini Aventador—which retails for more than $400,000—he asked Marine Technology to make him a matching boat.
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The result is a bright yellow beast in the water that has the same fighter-jet wedge shape and nearly the same speed as the Aventador.
The company modeled every detail of the boat—from the taillights and headlights to the steering wheel and air vents—on the Aventador, Gallagher said. Even the dashboard is the same, with the iconic "start" button hidden under a small red lid.
Under the hood, however, the floating Aventador boat makes the driving Aventador look puny. Instead of a 700-horsepower engine, the Aventador boat has two 1350 Mercury, twin turbo engines, creating up to 2,700 horsepower. The boat is "capable" of going 190 mph, Gallagher said. Of course, you probably wouldn't be in the water anymore at that speed.
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The total cost of the floating Aventador is about $1.3 million. "The engines alone cost more than the car does," he said.
Mercedes-Benz has also gotten into the supercar-boat game. While the company was creating a concept car inspired by the Gran Turismo driving simulator, it also teamed up with Cigarette Racing to make a matching boat.
Cigarette's 50-foot "Vision GT Concept" has twin 1,650-horsepower Mercury Racing engines and a lightweight body that can help the boat reach top speeds of 140 mph.
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It's got carbon fiber dash panels with silver-face gauges, Bluetooth, and high-tech navigation and audio.
Price tag: $1.5 million.
Skip Braver, CEO of Cigarette Racing, said that he's had "strong interest" from several potential buyers.
"The interest has been incredible," he said.
Ferrari doesn't seem to have gotten into the act in an official way. But photos of a $4 million LaFerrari Boat—inspired by the $1.4 million LaFerrari—have recently been making the rounds on the Web. The boat is powered by two 900-horsepower Volvo engines and has five flat-screen TVs and plush leather interiors.
A LaFerrari powered by Volvo? Sure, it's a stretch. But since the LaFerrari is already sold out, perhaps you have a better chance of buying the boat.
—By CNBC's Robert Frank. Follow him on Twitter @robtfrank.