There is a ton of Urban Legends, but really to see one posted and reposted that has been discredited more times than I can count means this person isn't paying attention or is incredibly immature. So after I saw an oldie but a goody posted, I thought there really are some Urban Legends you shouldn't post. So as a public service here are a few that are just plain wrong.
The Killer in the Backseat. This is the one that showed up last night. It may be inspired by one incident that occurred in 1964, but there are no other incidents...zero incidents since then. This myth involves a woman who is getting gas when the attendant calls her back because of a problem with her credit card. He brings her into his booth where he informs her that he could see a hulking killer in her backseat. He calls the police, and she is saved. There are variations such as a guy who sees an evil killer at a stop light or hiding under the car ready to slash her ankles. All of them involve a woman being saved by a man from an evil man. Here is the Snopes story. This is one of those stories that are as old as the Hook Man or Bloody Mary urban myths. Hopefully you are not as naive to believe these stories either so don't post this one.
Another along the same line is the Deadly Pullover. Gang members in this story or actually wannabe gang members flash their headlights on and off at random cars to get them to pullover so the wannabe can kill the occupants. It is the last step in their gang initiation. The myth is completely baseless, but like its brethren myth where gang members bump a random car or stop someone asking for directions, it is the best kind of myth because it relies on fear mongering which is something that is easy to do, especially on the internet. Heck, politicians and activist groups have been using the technique for years.
Then there is the Kidney Heist or organ thieves. This one of those stories that just won't die because it appears again and again on TV show like Law and Order. There is no organization in the US or in other countries that have plans to drug you and steal your kidney or any other viable, transplantable organ. Most recently there was a case in 2008 when a group of people was arrested in India for taking laborers into a secret underground medical facility to steal their kidneys. Charges were dropped when it was discovered that the accuser still had all his organs including kidneys in tact and there was no underground facility.
The worst of these though, is the My Sick Child hoax or the Charity Hoax. This is the one where you are asked to 'like' and 'share' a picture of a sick child and some organization or Facebook will pay $1 for each. This is a sick scam. First there is no one paying for 'likes', and second, the poor child is usually a stolen pic someone's sick child used without permission and often a torment to the real family who has to see this pic posted all over the internet. The child has cancer, a tumor, a deformity, etc. It is a horrible abuse of children and their families. It is a hoax. Anyone that would use pictures of these children for their sick hoax needs to not only lose the pic but have their account pulled. You post this hoax on my timeline, and I will report it. I suggest you do the same when you see it. Don't spread these pics. While Facebook has been very slow to respond to this hoax, if enough report and keep reporting, maybe we can make a difference. You can report them here. Here is a list of Charity hoaxes from hoaxslayer.com.