When you speak of bad luck, it is said that one should always knock on wood. Also knocking when speaking of good luck apparently helps with having good luck. This is an old Celtic tradition related to belief of wood spirits.
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In Asia, the digit 4 never appears in any Nokia handset model number, because 4 is considered unlucky in many parts of Southeast/East Asia.
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An acorn should be carried to bring luck and ensure a long life.
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It's bad luck to leave a house through a different door than the one used to come into it.
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In some parts of England, rum is used to wash a baby's head for good luck.
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Before traveling a person should, apparently, sit on their luggage. (Russian)
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According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
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Some motorcycle enthusiasts hang a biker's bell from a portion of their bike to protect themselves from evil road spirits.
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