Mayo, a history graduate from University of Warwick, used the day's date each morning to regurgitate facts and events which had happened on that date in years passed.
As a quirk, he would often add a mildly cynical punchline to each of the stories he recounted, and then would get his "crew" (female co-host, newsreader and producer) each to guess the age of living celebrities who were born on that day.
A tie-in book of the same title was published, initially just to give away on the show to a daily winner who rang in with the correct answer to a question posed by Mayo about a specific person or event of relevance to that date.
Perhaps the most famous part of the feature was the music used to soundtrack it; a looped instrumental version of the George Michael hit I Want Your Sex; the full version of which had been banned from broadcast by Radio 1 when it was released in 1987.
The feature ended when Mayo left the breakfast show, although when he switched to the mid-morning programme, he revived it in part with a spot called Dead Or Alive?, where he would ask listeners whether celebrities or known figures born on the date in question were still living or not.
Mayo now works for BBC Radio Five Live and no longer does any features which show off his passion for history. However, the feature is often heard in one form or another on many commercial radio stations.