NEW YORK, NY.- The most impressive works of art often took months or even years to complete. Artists pour their knowledge, creativity and emotions into their projects. Their finished products are filled with meaning and thus personal importance, the value of which cannot be appropriately measured, at least until they sell to the highest bidder. The following famous works of art cost a lot of money, held a lot of significance to the art community, and were unfortunately damaged due to carelessness, negligence, anger or pure insanity, likely causing the creators great despair — or to roll over in their graves.

1. Fountain (1917), Marcel Duchamp: A gifted artist can make almost any object meaningful. Take Duchamp’s Fountain, a white Bedfordshire model urinal he purchased in New York in 1917. Initially, there was debate as to whether it was actually art, as he submitted it to a Society of Independent Artists exhibit, which opted not to display it; however, in 2006, it was valued at $3.6 million. That same year, it was vandalized with a hammer by a 76-year-old performance artist, leaving it slightly chipped. The same man urinated in the piece 13 years earlier when it was on display in Nimes, France. The piece remains a hot target today.

2. Night Watch (1642), Rembrandt van Rijn: Night Watch could’ve used its own militia to watch over it through the years. Showcased at the Rijksmuseum in Amsterdam, the painting has been targeted on a few occasions. In 1911, an unemployed navy cook unsuccessfully attempted to cut it with a knife. In 1975, a schoolteacher more effectively slashed zigzag lines into it, and although the painting was restored, traces of the damage are still evident. The man was later determined to have a mental disorder and he subsequently committed suicide. In 1990, a man sprayed it with acid, but guards acted quickly and the painting was saved from destruction.

3. Danae (1636), Rembrandt van Rijn: One of Rembrandt’s favorite pieces, Danae depicts the mother of Perseus — from Greek mythology — as she welcomes Zeus, his father. The eight-by-ten-foot painting nearly met its demise in 1985, when a deranged visitor to the Hermitage Museum in St. Petersburg, Russia, where it has been housed since the 18th century, brandished a knife and proceeded to slash Danae’s lower stomach and upper thigh. He capped off the dramatic episode by tossing sulfuric acid onto the canvas, causing the original paint to splatter and run. The painstaking restoration took 12 long years to complete, and fortunately, the painting is again on display.

4. Rokeby Venus (1647-51), Diego Velazquez: Velazquez was a master at realistically depicting human form, as evidenced by his painting Rokeby Venus, in which the goddess Venus is lying in bed in a seductive pose, looking into a mirror held by her son Cupid. Venus was nearly ripped to shreds in 1914 by militant suffragette Mary Richardson — who later in her life became the head of the women’s section of the British Union of Fascists — following the arrest of fellow suffragette Emmeline Pankhurst. She entered the National Gallery in London despite previous warnings of a possible attack and left seven slashes mostly across Venus’s back. Richardson was given the maximum six-month sentence for the deed.

5. The Virgin and Child with St Anne and St John the Baptist (1499-1500), Leonardo da Vinci: Also hanging in the National Gallery in London is The Virgin and Child with St Anne and St John the Baptist, a black and white charcoal and chalk drawing executed by da Vinci more than 500 years ago. It was valued at $35 million in 1987, when a man attempted to shoot it with a sawn-off shotgun intending to show his anger at the ”political, social and economic conditions in Britain.” The blast shattered the protective glass, causing a six-inch tear in the Virgin’s robe. Numerous glass fragments and loose bits of paper were removed in the restoration, which, as usual in such cases, couldn’t completely bring it to its original form.

6. Portland Vase (30-20 BC), Maker Unknown: The Portland Vase couldn’t make it two millennia without being shattered, but it did outlast most household vases by about 1,865 to 1,875 years. The exquisite cameo-glass vessel, featuring depictions of humans and gods, was discovered near Rome in the 16th century and has been in the British Museum since 1810. In 1845, a drunken man threw another sculpture onto the Portland’s case, smashing both. Some fragments of it were lost and later found, but added after its first restoration. Its final restoration occurred in 1988 and 1989, and now little damage is visible.

7. The Little Mermaid (1913), Edvard Eriksen: Because The Little Mermaid is one of Copenhagen’s main attractions, the 4-foot statue has been defaced for a multitude of reasons — often political — and as a result, has essentially been rebuilt. Since 1964, its head has been sawed off, stolen, replaced and stolen again; its arm has been sawed off and stolen; it has been blasted off its rock base by dynamite; and it has been covered with just about every color of paint. It’s quite possibly the most victimized piece of art in the world.

8. Pieta (1498-99), Michelangelo: Revered by the religious and those who merely appreciate classic sculptors, Pieta is a prime attraction at St. Peter’s Basilica in Vatican City, as it depicts the body of Jesus in the lap of Mary after the Crucifixion. During its more than 500-year history, the most significant damage sustained to the work occurred in 1972, when a crazed geologist attacked it with hammer while yelling "I am Jesus Christ." Many of the pieces, including Mary’s nose, were taken by onlookers and not returned. It was restored with material from Mary’s back and now is protected by bullet-proof glass.

9. The Actor (1904), Pablo Picasso: Think of the costliest accident in your life in terms of monetary value, and now compare it to the 2010 incident in which a New York woman fell onto The Actor and caused a six-inch tear vertically along its lower right-hand corner. The 4-feet-by-6-feet painting, depicting an actor on stage wearing in a commedia dell’arte, had been on display at Metropolitan Museum of Art since 1952, and is estimated to be worth $130 million. Of course, because it was an accident, she wasn’t punished — or required to foot the bill. But she certainly created lots of grief.

10. Le Reve (1932), Pablo Picasso: Four years before The Actor suffered its fate, a painting portraying Picasso’s mistress Marie-Therese Walter, was damaged by its owner Steve Wynn, an American casino owner and real estate developer. Just before he intended to sell it to hedge fund manager Stephen Cohen for $139 million, which would’ve made it the priciest piece of art in history, he punctured the picture with his right elbow, creating a two-inch tear in Walter’s left forearm. Wynn, who suffers from retinitis pigmentosa, decided not to sell the painting. The repair cost $90,000.