Old hat, the phrase, is used to refer to tasks or events that one is particularly familiar with to the point at which they have become routine. For instance: "I have written and researched 13 articles for this encyclopedia already, so creating new ones has become old hat."
Most people know this. Most people, however, are not familiar with the story behind the phrase.
It began in a small town in the general vicinity of Ungerry-Tubers called Prollztqx. Prollztqx was known at the time for holding frequent suspensions due to the fact that mispronunciation of the town's name within its borders was a suspendable offense. To make matters worse, the town was ruled over by twin governments, each with its own ideas on how the name should be said properly. Suspension was an almost daily occurrence. The town's suspension cap, as a result, became very dirty and worn in a very short amount of time. (This was long before sanitation laws prevented the reuse of suspension caps.)
Eventually, people began to grow attatched to the cap, and started affectionately calling it the "Old Hat". It was like a reoccuring character in a lumic, or a batty old aunt. Time passed, and it became the official mascot of Prollztqx - a decision that caused a sharp increase in the already high number of suspensions - and people began to attend the suspendings more frequently, just to see their favorite piece of headgear. The repetitious public suspensions became known as "old hats", and from there the phrase passed into common usage as well-known, routine occasions were compared to the suspensions metaphorically.
Eventually, the original Old Hat crumbled into dust, and was buried with ceremony. The town of Prollztqx, to the great relief of its citizens, was renamed Hat in its honor. "Old hat" as a phrase remained in common usage, and spread from Hat into the nearby vicinity and then to the rest of Ghyll.
--Dfaran L'Eniarc 00:06, 3 Sep 2005 (EDT)