The idea of finding a rare and valuable item hidden away somewhere is one of the joys of collecting, and every day it drives people to auction houses, car-boot sales and charity shops in search of hidden treasure.
Many such stories turn out to be urban myths. The legendary Harley Davidson motorcycle signed "To Elvis, love Priscilla" has already been 'discovered' in more than 200 barns across America (although nobody claims to have seen him riding it yet).
However there are some stories that turn out to be true...
It may seem unlikely, but sometimes the most incredible objects can turn up where you least expect them. Here are our top five amazing discoveries: arts and antiquites found in the strangest of places....
1) The Buffalo Michelangelo
The painting was known as "The Mike" in the Kober household, a family joke that looks set to prove the old adage: it's funny because it's true.
For years the painting hung behind their sofa, enjoying the wear and tear of family life (including being the target for a tennis ball or two). The family had always regarded the painting in their living room as a Michelangelo, an heirloom passed down from their German ancestors, but it wasn't until retired Air Force Lieutenant Colonel Martin Kober decided to do a little research that the amazing truth was discovered.
With help from Italian art historian Antonio Forcellino, a series of X-rays and chemical pigment analysis the painting has been shown to (almost certainly) be the work of Michelangelo. The painting is an unfinished 'Pieta', a depiction of the crucified Christ in the arms of his mother Mary, which Forcellino believes was painted in 1545.
If verified, experts believe its value to be in the region of $100m - $300m.
2) The Qing in the attic
You might expect to find many things in an attic. Old board games, tins of paint and a box of tangled-up Christmas lights would be likely. But the world's most expensive piece of Chinese art? Possibly not.
But earlier this year, a brother and sister from North London discovered a vase during a house clearance that grabbed headlines around the world when it sold for an incredible £43m.
The vase, believed to have originated from the Imperial Kilns of the Qing Dynasty from around 1740, was discovered amongst the belongings of their late parents where it had lay hidden since the 1930s.
Originally valued at £20m, the vase smashed it's estimate and was sold to a Chinese collector who planned to return it to China.
3) The lost Picasso collection
In September of this year, a 71 year-old electrician named Pierre Le Guennec strolled into the Paris office of Claude Picasso with a suitcase under his arm.
Inside was a remarkable collection of 175 'lost' Picasso works, dating from 1900 - 1932, which Le Guennec claimed to have been given to him by the artist in return for installing burglar alarms in his various homes.
Although the works were undoubtedly genuine Claude was suspicious of their true origins, and when police raided Le Guennec's home they discovered a further 96 works. None have the customary signature and date with which Picasso marked all his artistic 'gifts', and an investigation into how the works were acquired is ongoing.
The one thing that can be said for certain, however, is that the incredible 'lost' collection has an estimated value of up to $79m. Who gets their hands on it is another matter entirely....
5) The Staffordshire Hoard
His metal detector cost just £2.50, but what it found was worth £3.3m. Terry Herbert had spent 18 years scanning the countryside for a buried treasure or two, but in 2009 he found an entire hoard.
The vast haul of Anglo-Saxon gold and silver was found buried on farmland in Staffordshire, and contained 1,600 items including swords, helmets and trophies. It had originated in the Mercian Kingdom which thrived in the area during the 7-8th century, and contained 5kg of gold and 2.5kg of silver.
It was valued at £3.3m by the independent Treasure Valuation Committee, a figure to be split between Mr Herbert and Fred Johnson, the farmer on whose land it was found. Which adds up to a £1m return on a £2.50 investment.
5) The hidden Declaration of Independence
In 1989 a financial analyst from Philadelphia bought a picture from a flea market because he liked the frame. The value? Four dollars.
When he removed the picture he discovered a folded document inside, which appeared at first glance to be an old reprint of the Declaration of Independence.
But further tests proved it to be only the 25th known surviving copy of the Dunlap Broadsides - 200 manually printed copies, produced hours after the declaration was signed to be sent to the 13 colonies and beyond. The document was later sold at auction in 1991.
The value? $2.4m.
People love to imagine that a family heirloom could turn out to be priceless, or that they could discover a copy of Action Comics #1 at a car-boot sale. It's part of the magic of being a collector. But as our top five shows, there are always treasures out there somewhere just waiting to be found...
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