The one that got me recently was an ad in the Washington Post for "seed" coins, based on a story about Jesus in one of the Gospels. Basically low demonination Roman coins that aren't exactly uncommon, but given a jumped up back story to attract religious minded idiots willing to pay more than their worth for a pair of coins that were "Minted during the life of Jesus and showing the religious symbols of the time!"
Y'know, symbols of Zeus, Mithras, the Emperor... headdesk