Century of the Rat
In Feet of Clay it is posed by Doc Pseudopolis, President of the Guild of Gamblers that the next century would not be the Century of the Anchovy but instead the Century of the Rat. This is met with no protest by the Guild leaders but is not mentioned again in the Discworld Novels. In both Going Postal and Making Money they claim that it's the Century of the Anchovy
Feet of Clay: "However, Doc Pseudopolis of the Guild of Gamblers put on a careful poker face and said, “Yes, but the tricentennial is coming up. And in a few years it’ll be the Century of the Rat. There’s something about centuries that gives people a kind of fever.”"