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 some parts of England, rum is used to wash a baby's head for good luck.
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Placing keys on a table is considered unlucky. (Sweden)
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According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
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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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If one walks underneath an open ladder it is said to bring bad luck. Sometimes it is said that this can be undone by immediately walking backwards back underneath the ladder.
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Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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An acorn at the window will keep lightning out
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