...you must burn an old shoe. If you don't have it, salt may be burned instead :))
after the change to the gregorian calendar in Greece at 1924 Greeks say that the καλικάτζαροι - kalikatzari (Christmas trolls) stopped coming to trick people because the days that the trolls were coming were blessed days (Christmas is earlier than it was) so the trolls never make it to come. The superstition says that the kalikatzaroi are affright of the fire, the sound of burning salt, anything holy, holy water, the cross etc. Also they want to count and calculate anything so they are afraid of the sieve, if you leave it outside at night, they have to count the holes, so they stay there to do it and the morning comes, they hear the rooster and they disappear because they also are have fear for the morning sun.