well, no but u r right in that it does seem like some mountain spell binding....when i was a kid my mom found a drunk man who'd baby sit me for a six pack a day.  back then that was like less than two bucks.  she'd drop me off in the mornings and by mid morning he'd be drunk and tell me to go outside to play.  so during my first week at his house, i went out side and took out one of my shoestrings and made a noodle out of it and was walking around the neighborhood with a couple rocks. a man from his garage yelled out to me, he had a thick accent, some what turkish, i do believe.  he asked what i had and i told him a sling.  he walked over to me and asked to see how i knotted the string and noticed my shoestring was the sling and not in my shoe.  then he told me who and what he was.  he was an archeologist and historian, he spoke a couple languages...but most importantly, he was as slinger.  he was only in the area because of the sling type in discussion.  all that was known of it was legend, one statue with one, so that showed no details, but during a dig somewhere, one corner of a socket was found.  soon he found out that a picture existed of what was thought to be one in a library close to where i lived then, so he flew over to check it out because the library would not send the book and it was one they did not even allow to be checked out.  he saw it and it was a picture of an old drawing that had one in it.   he was the one who figured out, from the corner piece found and picture, how to form the sling.  it is said to be called the byzantine sling because they used it, but is supposed to be older that they were.  the grain has to flow right for it to pass muster.  in the old legends it is said that a sling master, if allowed to pick his own ammo for the job, could be blindfolded, have a loaded sling placed on his fingers, throw with it and tell you from the feel of the rock leaving the socket if the grain was running right in the direction or not.  so it is more of an eastern european, northwestern asian thing.

i'd love to be able to show it to you.  it is hard to understand via written insruction.  i can explain it or try to, and come the end of the year perhaps can even put some video of it up for you guys.  i technically have to be cautious about that until around december for reasons i cannot go into but let me try to explain it.
  if you are right handed,twist ur left hand, palm under and away from you so that it's palm is facing left.  hold the sling in front of you, cup your left hand and with it still twisted, place the socket in it.  raise the sling up over our head and lower it behind you. at this point it should be diagonal across ur back, with ur right hand above ur right shoulder and ur left hand around ur left hip or bottom of rib cage.  raise ur right hand palm up and hold it high almost even with the top of ur head, and pull the other end snug with the left hand, raising it up slightly to make the sling barely bend at ur left elbow, but being kept taut. take care the sling is not twisted up....release with left hand and let the socket drop and swing behind you and then just over hand with popping wrist action.  it sounds more complicated than it is, but once understood it is a very accurate little toss that can generate some power when the full wrist action is properly utilized.  works great for turkey as, you can stand ready for long periods at a time by resting your throwing hand on your shoulder and when execute much of the motion is hidden behind the back.  lefties just switch it around the same way