Friday the 13th.
As Michael Scott once said, "I'm not superstitious I'm kind of stitious."
FROM WIKI: The fear of the number 13 has been given a scientific name: "triskaidekaphobia"; and on analogy to this the fear of Friday the 13th is called paraskevidekatriaphobia, from the Greek words Paraskeví (Παρασκευή, meaning "Friday"), and dekatreís (δεκατρείς, meaning "thirteen").
The superstition surrounding this day may have arisen in the Middle Ages, "originating from the story of Jesus' last supper and crucifixion" in which there were 13 individuals present in the Upper Room on the 13th of Nisan Maundy Thursday, the night before his death on Good Friday. While there is evidence of both Friday and the number 13 being considered unlucky, there is no record of the two items being referred to as especially unlucky in conjunction before the 19th century.
He [Rossini] was surrounded to the last by admiring friends; and if it be true that, like so many Italians, he regarded Fridays as an unlucky day and thirteen as an unlucky number, it is remarkable that on Friday 13th of November he passed away.
It is possible that the publication in 1907 of Thomas W. Lawson's popular novel Friday, the Thirteenth, contributed to disseminating the superstition. In the novel, an unscrupulous broker takes advantage of the superstition to create a Wall Street panic on a Friday the 13th.
A suggested origin of the superstition—Friday, 13 October 1307, the date Philip IV of France arrested hundreds of the Knights Templar—may not have been formulated until the 20th century. It is mentioned in the 1955 Maurice Druon historical novel The Iron King (Le Roi de fer), John J. Robinson's 1989 work Born in Blood: The Lost Secrets of Freemasonry, Dan Brown's 2003 novel The Da Vinci Code and Steve Berry's The Templar Legacy (2006).
Well, if you read all of that you're a better man than I am Gunga Din.
Here's the deal, I don't believe in luck, therefore I don't believe in bad luck. I do believe in Karma however. Karma is the force that encapsulates us and comes back and kicks us in the ass when we do something bad.
It's the reason Osama Bin Laden died in his pajamas terrified in an after midnight raid after a decade of living a solitary life of fear in his bunker.
It's the reason Adolph Hitler sat in his own bunker on that August 1945 day with his longtime girlfriend and came to the realization that he was about to be dragged through the streets like Mussolini if he didn't take his own life.
So believe what you want, watch those cracks when you're walking lest your mom suffer the throws of a broken back and should a black cat run across your path simply spin around three times repeating "It's going to be okay."
Because it will.