Hitchhiker's Guide to the Galaxy, The Easter Egg - Dirk Gently Reference

First, obtain a copy of "Life, the Universe, and Everything." Turn to page 5. At the top it is talking about a character called Wowbagger the infinitely prolonged. About two rows down it says "stare at the clock, the hands will move relentlessly on to four o'clock,and you will enter the long dark teatime of the soul."

This is a reference to Douglas Adams "Dirk Gently" series. The second book in this series is called "The Long Dark Teatime of the Soul."