Can anyone tell me why Friday 13th is considered unlucky? I've heard that it's to do with the crucifixion, the Knights Templar, Norse mythology, vikings and sailing. This sounds to me like a frightening combination if ever there was one, but it doesn't really help. Unless it's only unlucky because you have to try to wrap your brain around all of these things in one day, but I would consider that torturous rather than unlucky...
Anyway. Thoughts, anyone?