Placing keys on a table is considered unlucky. (Sweden)
3
Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
225
At times, a horseshoe may be found above doorways. When positioned like a regular 'U' it supposedly collects luck. However, when it is positioned like an upside-down 'U' the luck supposedly drains.
78
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.
75
According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
24
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.
208
Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
Many believe that if all of the candles on a birthday cake are blown out with one breath, while making a silent wish, the wish will come true.
298