The most famous of all Greek superstitions with very old roots in Hellenic culture from the time of paganism is, by far, the evil eye. Paintings of Greek triremes over two thousand years ago have an eye painted at the front of the trireme in an attempt to ward off the Evil Eye. The Evil Eye is known widely throughout Greece and the Greek Islands. The Evil Eye is said to be able to strike anywhere without notice and no one can be the wiser.
Think back to a time when someone complemented you on how nice you looked only for you to have a painful headache immediately after. Happenings such as this are attributed to the Evil Eye. To ward off the Evil Eye several things can be done. An eye is painted into the middle of a blue charm; this charm is then worn as a necklace or as a bracelet. Blue beads can also be worn instead of the eye charm in the form of a necklace or bracelet. The reason the color blue and the painted eye are used is that both are thought to ward off the evil of the eye. Unfortunately people who have blue eyes are thought to be exceptional givers of it. Believers of the Evil Eye are weary of compliments received from a blue eyed person.
It is also said that a clove of garlic has the ability to ward of the evil eye. Many people keep the clove of garlic in their clothes or in their pockets.It is customary for Greeks to use Garlic to ward off evil. Garlic is believed to ward off demons and evil spirits in the same manner that incense does. Demons and evil spirits are believed to fear it. If you find garlic hanging in Greek businesses or houses it is there for the purpose of warding off evil.
In Greek superstition, if you sneeze it is believed that somebody is talking about you. Since you do not know who the person is you may try to figure out by saying out people's names. If you say a name and you stop sneezing it is thought that that is the person who is talking about you. Another way to find out who is talking about you is asking someone for a three digit number. You then add the three digits together and come out with another number. Using the final number, you count down from the start of the alphabet. The number you get must be less than or equal to the maximum characters in your alphabet, in the Greek Alphabet this is 24, in the English 26. If it is more you count the numbers together once again to find a smaller number. The letter the number falls on is the first letter of the name of the person that is talking about you.You can then think of people you know whose name begins with that letter.
Tuesday is considered the unluckiest day of the week for the Greek people. It was on Tuesday May 29th 1453 that the unimaginable happened and the city of Constantinople fell to the Osman Tribe, the "Ottoman Turks".It is often said that businesses that open on this day have a black mark against them, and many Greeks who believe in this superstition will not venture into a new business on a Tuesday. The number 13 is considered lucky by Greeks in the setting when it stands alone. However, when Tuesday and 13 are placed together they are considered unlucky in the Greek culture. So Greeks will watch out for Tuesday the 13th not Friday the 13th. It is the combination of the date "Tuesday" with the number "Thirteen" that is considered very unlucky to the Greek people.
Crows are seen as a bad omen, often foretelling death. Upon seeing crows cawing, it is believed that the crows are announcing the death of an individual. Greeks believing in this superstition will often say to the birds, "Go on your way, and bring me good news."
Source - GreekSpider
As far as I am concerned, I am superstitious to some degree. For instance, I believe in the evil eye. I remember an occasion when I was complimented by a friend while shopping. Soon afterwards I fell down and sprained my ankle! Although I love animals, I'd never have a black cat with green eyes for a pet. And I'd never make important decisions on a Tuesday 13. However, I don't consider sneezing a superstition, yet it's fun to play the alphabet game.
What kind of superstions do you have in your culture? Do you believe in them?