Image caption Sir Roger Moore died on 23 May at the age of 89

Did Sir Roger Moore invent the Magnum? That was one of the more curious rumours to emerge about the British actor following his death last month.

According to journalist Chrissy Iley, the James Bond star once said in the 1960s his one wish would be for ice cream company Wall's to produce a choc ice on a stick.

The company apparently sent him a version of his wish, and many years later they went on to launch the Magnum in 1989. The ice cream on a stick is now the world's top-selling ice cream brand.

Wall's themselves claim to have no knowledge of his purported involvement, telling the Daily Mirror it was no more than "a brilliant story".

But if Sir Roger did have a hand in its making, he would not be the first celebrity to have come up with a great idea or marketable product.

Harry Connick Jr

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He's a singer, a talent show judge and an occasional actor. Yet Harry Connick Jr can also lay claim to be the inventor of a valuable tool for orchestras.

While touring in the '90s, the popular crooner was so frustrated with his sheet music blowing away that he devised a machine capable of displaying music digitally.

One of the unforeseen benefits was the way it allowed him to make adjustments to his band's sheet music without generating reams of amended paper.

"Oh man, it's made my life easier," he told the New York Times in 2002. "I can write a new score in the morning and everyone has it on his computer screen in the afternoon."

Jamie Lee Curtis

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The Halloween star was one of cinema's most famous scream queens before going on to show her comedic chops in A Fish Called Wanda.

But the 58-year-old star of Trading Places and True Lies also holds the patent for a modified nappy with a waterproof pocket for baby wipes.

"It's called Dipe 'N Wipe," she revealed last year in an interview on America's National Public Radio.

"Before you take off the diaper, you peel off the tape, reach in, pull out the wipes, undo the diaper, check out whatever's going on, take the wipes, boom, boom, boom, Bob's your uncle, done."

Howard Hughes

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The billionaire mogul owed much of his fortune to the Hughes Rock Eater, a self-sharpening drill bit designed by his dad.

Like father, like son? Kind of. Where Hughes Sr made machinery for oil wells, his offspring devoted his energies to a prototype push-up bra.

Designed for 1943 western The Outlaw, the cantilevered garment was intended to enhance the already prodigious bust of leading lady Jane Russell.

Russell, though, found the brassiere uncomfortable and insisted on using her own instead.

Michael Jackson

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The late pop legend was famous for many things, from popularising the moonwalk to owning a chimpanzee called Bubbles.

What many don't know is that he helped create one of his most dazzling illusions - the gravity-defying, 45-degree lean he and his dancers pulled off while performing Smooth Criminal.

The feat was achieved with the help of a specially designed shoe, with a heel that locked into a retractable peg built into the stage.

Patented in 1992, the mechanism worked perfectly - apart from one time in 1996 when one of the heels came loose, sending Jackson flying.

Image copyright US Patent Office Image caption Drawings from Michael Jackson's patent application

Hedy Lamarr

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The actress born Hedwig Kiesler in Vienna in 1914 became a Hollywood star in the 1930s and '40s after appearing scandalously nude in German film Ecstasy.

Her most lasting achievement, however, took place away from the silver screen.

During World War Two, she helped invent a new means of guiding radio-controlled torpedoes that neutered the threat of their signals being jammed.

The technology, known as frequency hopping, is still used today to operate cellular phones, GPS, Bluetooth and WiFi.

Zeppo Marx

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The youngest of the Marx brothers spent much of his brief time on screen being overshadowed by flashier siblings Chico, Groucho and Harpo.

Yet he achieved far greater success as an inventor of a wristwatch that monitored the pulse rate of heart patients and emitted an alarm when their heartbeats became irregular.

Zeppo also founded Marman Products, an aerospace manufacturer that made the clamps that held the atomic bomb released on 9 August 1945 above the Japanese city of Nagasaki.

Similar clamps would be employed in 1962 on the Friendship 7 mission that saw the late John Glenn become the first American to orbit the Earth.

Julie Newmar

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Famous for playing Catwoman in the 1960s Batman series, Julie Newmar proudly declares herself on her website to be "an 11th generation American and a Mayflower descendant".

But there is no mention of the pantyhose she patented in the 1970s that were marketed under the name "Nudemar" and were said to offer "cheeky derriere relief".

"They make your derriere look like an apple instead of a ham sandwich," she told People magazine in 1977.

The US actress and singer, now 83, also patented a brassiere with hidden straps.

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