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Spying elite toys at the Cannes Film Festival

This epicenter for international cinema is also gathering point for elite global wealth and the perfect spot for companies to lay out their highest-end attractions.

The U-Boat Worx Mini Submarine sits outside the Carlton Cannes International Hotel. John Scott Lewinski

CANNES, France--The Cannes Film Festival wrapped up this weekend and I joined the throng of media shuffling wearily through the Nice airport and away from the perfect sunshine of the French Riviera--but not before having had a look at the obscenely expensive toys of the proverbial nouveau riche.

When not attending screenings, I had a chance to skulk around the Plage de la Croisette along the Mediterranean shore to spy big-ticket items soon to be for sale to those with the most disposable incomes.

I could not avoid the gold- and diamond-encrusted smartphone and tablet cases. In every case, no photography was allowed inside the elite boutiques featuring such accessories. Anyone taking a snapshot of an emerald-studded BlackBerry kit would only be scouting trouble.

So how much were these decorative doodads? A single refrain rules in shops like this: "If you have to ask, don't bother."

But not everything was under wraps.

Up and down the festival thoroughfare, tourists were on the lookout for stars shopping at Dior or Prada. Yet only one sight consistently had cameras snapping and couples popping over for commemorative photos: the 2012 Mercedes Benz AMG SLS Gull Wing. Clad in red brighter than any carpet in Cannes, this work of art stopped traffic outside the Cannes Carlton Intercontinental Hotel. As super cars go--especially those tooling around Cannes and Monaco, the new AMG SLS is affordable--coming in at around $200,000.

Not to be outdone, Ducati tucked its 2012 Diavel alongside the Mercedes. The $20,000 bike is powered by a Ducati Testastretta race engine with 162 hp and 94 pound-feet of torque.

Not too far from the red heaven on wheels, U-Boat Works had its personal mini-submarine on display. Essentially an underwater car, the unfortunately named U-Boat dives as deep as 100 meters with a maximum traveling range of 1,000 meters, depending on its layout. It sells for between the high five figures and $1.5 million.

I bought two but had to leave them behind. Have you ever tried to get a personal submersible through airport security?