Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
It's bad luck to leave a house through a different door than the one used to come into it.
143
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
A single magpie is considered a sign of bad luck. A Guide to the Scientific Knowledge of Things Familiar recites an old proverb concerning the incidence of bad weather when magpies forage alone and a possible scientific explanation for this.
49
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
Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
225
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
An acorn should be carried to bring luck and ensure a long life.
115