The yacht has “long been the classic indicator of someone who has so much money that he doesn’t need to make any more,” wrote Slate’s Daniel Gross last week.

And while Gross was talking largely about America’s business class boat owners, the same rule applies to Australia’s super rich, super yachting corporate bigwigs.

So who are our top corporate yachties?

Frank Lowy: The Westfield boss is the undisputed king of Australia’s harbours, with his $110 million 74 metre Ilona IV (pictured below, via Yachtforums.com), named after his mother and often spotted parked between naval ships at Garden Island near Woolloomooloo. Ranked the 32nd biggest yacht in the world last year by Power and Motoryacht magazine, it features a pool, 18 guest bedrooms, a gym, massage room, cinema, mahogany stateroom and concealable hydraulic retractable helipad.

Reg Grundy: The media baron ranks right up there with his $90 million 71 metre tinnie Boadicea. Berthed, until recently, at Rozelle Bay Superyacht Marina, it is more often spotted in the world’s most exclusive holiday waters from the Caribbean to the Riviera. Manned by a crew of 24, it has ten luxury suites and the obligatory cinema.

Lang Walker: The recently retired billionaire property developer is yet to sail the latest version of his superyacht Kokomo, which has been under construction in Auckland for the past two years. Apparently he has already received offers to buy the $30 million, 52 metre boat, described as the “Rolls-Royce” of luxury yachts. We can expect to see the Redman Whiteley Dixon-designed Kokomo IV in our waters around September. It has a large saloon and formal dining area for up to ten guests.

The Packers: The late media mogul Kerry Packer spent a reported $20 million ten years ago converting this 87 metre former ice-class tug into a world cruiser, known as the Arctic P. Now worth about $13 million, it features a swimming pool and helipad.

Lindsay Fox: The trucking billionaire’s sleek Sunseeker Predator 108 was still being built last November, but is reputedly a speedboat worth $10 million, with a separate dining and lounge area with lots of visibility and a glazed hard-top sunroof. Other features include a spa on deck, granite bathroom floors and countertops and satin cherry wood finish throughout.

Solomon Lew: The Melbourne businessman’s 45 metre ocean-going yacht Texas is probably currently plying the Mediterranean, as it does each Melbourne winter.

Bob Oatley: The billionaire wine entrepreneur is another keen competitive sailor — his Wild Oats XI, which won last year’s Sydney-Hobart race in record time, is the hot favourite to follow up his 2005 win at this year’s Hamilton Island Hahn Premium race. And apparently he’s paid handsomely for the speed.

Lachlan Murdoch: The son of Rupert is a keen sailor — often spotted at the annual Hamilton Island’s race week. Indeed his 82 foot luxury cruiser Ipixuna powered to her second easy line honours win in the Premier Cruising class of the 59 nautical mile 2006 Club Marine Edward Island Race just last weekend, with Lachlan at the helm.

Greg Solomon: The man behind the music piped into supermarkets was having his dream boat — an 18.9-metre pilot house vessel – constructed in China last year. It was due to hit Australian waters in February this year and is reported to be spectacular.

Meanwhile, here are some other Hamilton Island regulars you might expect to see at this year’s event: founding director of Ipac securities Paul Clitheroe, Blackmores founder Marcus Blackmore, Hills Hoist heiress Tess McGrath and Macquarie Bank Property Head Stephen Girdis.

Got any additions or amendments for our superyachting corporates list? Email [email protected]