On occasion of yesterday's leap day, I remembered that Tolkien had devised his own calendar system, called Shire-reckoning, that I find very elegant.
Compared to our own calendar system it is more consistent and easier to memorize, since it maintains the same number of days in each month (and the Hobbits even managed to have a consistent weekday for any given day of the year), thanks to special days that are not assigned to a specific month.
On leap years such as 2024, another such special day is inserted in mid-summer; so in a few months we'll have a so-called "Overlithe" in the middle of the Yule festival. Apart from its simplicity and elegance, this also seems like something a Hobbit's mind would come with - solving a problem by having one more day of festivals.