Credit where it's due: Barry Diller knows how to vacation. The IAC boss is tightfisted at headquarters, but his holidays are plenty decadent. There's the corporate jet; the giant boat; tropical beaches; and a set of young blonde twins.

Diller's sumptuous tastes are legendary, and the legend has only been bolstered by the spending totals that have emanated from the CEO's internet holding company, like the $4,600 per day IAC spent on his personal travel in 2009. That hedonism annoys Diller's employees, especially now that they haven't seen any raises for three years running—or so we've been told.

But numbers don't paint the picture of Diller's lifestyle — or aggravate the CEO's detractors — nearly as well as pictures do. And for pictures you could do a lot worse than Bryan Fox's Facebook album of Diller's 2009 Thanksgiving getaway to Papua New Guinea, which was recently forwarded to us by an IAC mole. The photos provide an inside look at an enviably posh vacation spent in the company of enticing companions.

The aerial leg of the vacation, apparently conducted via IAC's $45 million Bombardier BD-700, brought together a group of Diller consorts including the media mogul's old friend Sandy Gallin, a former talent manager who once repped Michael Jackson and Barbra Streisand and who, along with Diller and David Geffen, has long been considered a member of Hollywood's gay mafia; Gallin's sometime travel companion Aaron Fox, a young blonde tennis instructor from Los Angeles (favorite TV show: HBO's Hung); Fox's twin brother Bryan, an actor, on whose Facebook these photos were posted; and a couple of other unidentified young men who appear more than happy to travel in style to the other end of the earth.

After disembarking from the IAC jet on the island, the boys then transferred to Diller's 300-foot boat, the world's largest sailing vessel, which the media mogul bought for $200 million several years ago.

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Then came some watersports, including snorkeling, waterskiing, and high-diving off the massive boat's bow.

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There was also some jet ski action. Diller, for once, let go of the driver's position, riding pillion and holding on to twin Aaron during a romp around a green-watered inlet.

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The trip seems to have loosened everyone up: Diller is seen hanging out on the beach, taking walks with the twins, and playing a game of backgammon aboard his boat:

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Of all the people on the trip, it's Gallin who seems to be having the most fun. Here he is pinching the nipple of one of his 50-year-younger companions.

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The photos aren't limited to the daytime hours. Here Diller sits with Bryan and takes in the sunset:

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The men would later travel to New Zealand, where, according an album Bryan uploaded in March of this year, Diller's wife, fashion designer Diane von Fursternberg, and a group of friends hung out. (Diller and von Furstenberg have an arrangement.)

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All in good fun, it would seem. But given IAC's lackluster stock performance, shareholders must be wondering whether they should subsidizing Diller's holiday temptations. Employees certainly are; wrote one, cheekily, "Barry loves to spend time with his boys. Let's face it, that costs money and IAC employees must understand these sacrifices."

It's hardly surprising that eyebrows were raised earlier this year over IAC covering $1.7 million in Diller's 2009 personal travel costs. These photos aboard the IAC jet—which include appearances by the Fox twins, Gallin, and artist/actress/socialite Ahn Duong—hardly show anything furthering the company's financial interests:

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It's not clear how Diller spent Thanksgiving 2010, but if this year's Turkey Day was anything like these pics from last year, Diller should be putting in a hefty expense report just in time for Christmas.

Speaking of the New Guinea boys, we're awfully curious about the two strapping identical ones. It's unclear what Diller's relationship with the Fox twins is, but it's worth noting that Bryan is one of only 59 friend connections Diller has made on Facebook, putting him in the elite company of Facebook CEO Mark Zuckerberg, Dell Inc. CEO Michael Dell, Condé Nast heir Steve Newhouse and other tech and media bigwigs. Bryan acted in a Los Angeles play called the Columbine Project a couple of years ago, and Aaron appears to work as a tennis instructor. He even filmed a couple of jokey lessons which can be found on YouTube (see here and here). But judging from their Facebook pictures, the twins have a very wide-ranging social network well stocked with notable people.

Those featured in their collection of photos (see below) include Larry Ellison, whose aspiring moviemaker son is name-checked as another buddy; David Geffen's youthful boyfriend, Jeremy Lingvall; fashion designer Valentino and his longtime business parner/boyfriend, Giancarlo Giammetti; Bravo honcho Andy Cohen; Adam Shankman, the director of such movies as Hairspray, A Walk to Remember and Bringing Down the House (and a judge on Fox's So You Think You Can Dance); Billy Sammeth, a talent manager who once worked for Gallin and spent 20 years representing Joan Rivers; and Ricky Van Veen, the co-founder of College Humor which was acquired by Diller's IAC.

The Fox twins' travels with Gallin and his friends have taken them beyond New Guinea and New Zealand to Tahiti, the Caribbean, the Mediterranean, Paris and London. That's quite a life, and there's no small amount of envy from friends in the comments on their Facebook profiles.

What's the deal with these well-traveled and well-connected young lads? If you have any more info, we'd love to hear from you.

Update: An IAC spokeswoman said the company has been giving some raises during the past three years; our original source said it was managers who have been frozen out of raises and bonuses, unless they get a promotion or title change.

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Previously:

Barry Diller's Secret Opulence