Did I have a harmonica, hell yea, that thing is in it's own box and just the act of reaching for the box now puts my players on edge, if you cant play the harmonica however a stratigic recording of Enrio Morricone's "the man with the harmonica" Works wonders, downloadable in abundance from kazaa or any such server.
Another good twist was that the ferryman appears different to everyone, to regular folks he appears as a weathered cowboy wearing a hat and plyin his harmonica, to voodooists they see the Baron Samidi, China folk see a shimmering white lady in flowing gowns with incredibly long nails and injuns see a brave come to escort them to the hunting grounds.
If anyone wants any more info on how I incorporate this please ask as ill take the time to write a more comprehensive email.
regards
Peter King