It has been billed by some as the unluckiest day of the century, even prompting the producers of the classic horror remake, The Omen, to schedule its release to coincide with the date.
While readers waking up today - the 6th day of the 6th month of 2006 - might be forgiven for taking extra care as they go about their business, scripture scholars have played down the date's significance.
Among the speculative bets, being offered by bookmakers Paddy Power, as to what might happen today are: the M6 to be closed for unexplained reasons all day (66-1); all number 66 buses in Britain and Ireland to break down (66-1); the World Cup to be stolen (as happened 40 years ago) (100-1); and the first baby born in Dublin's Coombe maternity hospital to be named "Damian" (100-1).
A spokesman for the company acknowledged the amount of money wagered on such bets is usually small, with the whole issue seen by most people as a "bit of fun".
However, such is the weight being given to the date that the remake of the 1976 Hollywood horror film The Omen, is scheduled for release today.
The film, in which a US ambassador learns that his son is the Antichrist, has already met with a degree of misfortune.
Last March, it was forced to move filming from Croatia to Ireland after sets were vandalised and burned down.
The director, Dundalk-born John Moore, told The Irish Times at the time that he blamed the Catholic Church in Croatia for a campaign against the film.
Fr Martin Hogan, a well- known scripture scholar and lecturer at the Mater Dei Institute in Dublin, said the symbolism of the number 666, and its associations with Satan, have their origins in the Book of Revelations.
According to Jewish traditions, the number seven would be regarded as the "perfect number", he explained. By comparison, the number six, one short of this, is seen as a negative, "imperfect or incomplete symbol".
If there are three sixes, this negative is multiplied to the power of three and is a symbol of Satan. "It is the number that is on the beast in the Book of Revelations," he said yesterday. "It is a very negative symbol, associated by the author with the Roman Empire."
While people down the ages have and will use the symbols of the Book of Revelations for their own means, Fr Hogan believes individuals should not be particularly concerned about the possibility of meeting misfortune today.
"People can draw to themselves all kinds of interpretations that are not necessarily in the text," he said. "There is no theological justification for thinking the day [June 6th] is any more unlucky than any other day."