Every year growing up a favorite aunt would send us a paper Advent calendar to help us count down the days until Christmas (and her holiday visit). When I eventually had a family of my own, we purchased a wooden box with 25 little doors, and had fun filling it with little toys and candies for our children to open each day.

As much fun as we have had with Advent calendars, I really shouldn’t have been surprised at the wide variety of forms that these calendars take in the U.S. patent collection, but I was and perhaps you will be too.