Just off the coast of Massachusetts is the tiny island of Nantucket — where some of the nation's wealthiest individuals own summer vacation homes, from Google's Eric Schmidt (net worth: $13.8 billion) to former GE CEO Jack Welch.
There's also "Harbor Hill," a waterfront vacation compound on the island, recently listed for $42.5 million.
From a bird's eye view, the 18,000-square-foot residence looks like a cluster of 12 separate cottages. "Each structure is very reminiscent of classic New England architecture," says Sotheby's International Realty broker Donna Barnett.
But one step inside, you'll observe that each "cottage" is actually a different room within the mega-home, connected by enclosed breezeways. In other words, there's a structure just for the great room, dining room, kitchen, master bedroom and so on.
It's also a smart home: "Each room has an iPad that controls everything: the TVs, the heating, the cooling, the music, the lighting," says Barnett. "The technology alone is worth is $2.5 million."
The owner, a telecom entrepreneur based in Palm Beach, Florida, has his high-tech touches everywhere — in the master suite a covert that TV rises up from the floorboards.
When the owner wanted to watch an even bigger screen, he would head down to the mega-home's state-of-the-art subterranean movie theater.
"It's unlike any other movie theater on the entire island," Barnett says.
While most homeowners would probably conceal the hardware and wiring in their homes, this tech-loving owner was so proud of the "brains" of this house, he had it all enclosed in an air-conditioned glass room and lit it up like a giant work of art.
The 23-room summer compound also has two separate cottages out back — one for the pool house and the other for the guest house — with a private gym, steam room, and sauna.
"People come to Nantucket to escape, to unwind," says Barnett. "This is the perfect property to do that in."
Want more mansion inspiration? Watch CNBC's "Secret Lives of the Super Rich" on Apple TV and On-Demand.
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