An acorn at the window will keep lightning out
93
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
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.
78
If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
394
Placing keys on a table is considered unlucky. (Sweden)
3
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.
105
Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
117