Opening an umbrella indoors is said to result in 21 days of bad luck. Some traditions hold that it is only bad luck if the umbrella is placed over the head of someone while indoors.
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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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The superstitious symbolism of a black cat crossing one's path is dependent upon culture: some cultures consider this a sign of impending bad luck, while some cultures consider this a sign of impending good luck.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
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It is bad luck to put new shoes on a bed (or a table) (comes from the tradition of dressing a corpse in new clothes and shoes and laying them out so everyone can give their respects) - (UK)
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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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Before traveling a person should, apparently, sit on their luggage. (Russian)
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