Then there's this story doing the rounds on email that has also been reported on the BBC's site.
The 32-year-old victim was walking on King Street at about 1800 GMT on Friday when she was approached by a woman. She gave her some change but the offender then grabbed her arm and scratched it with an unknown implement.
The story is harrowing and the implications that there are seemingly civilised, well-dressed muggers with sedatives and syringes is horrific. Two people I know claim they know the woman concerned. Yet I'm still inclined to think it's another urban myth.