You are familiar with the periodic table.
You may be familiar with the periodic table table, invented by Theo Gray. The top of this four-legged table is itself a periodic table of the elements. The invention led to Theo being awarded the 2002 Ig Nobel Prize in chemistry (and indirectly led to other things, including his becoming a columnist for Popular Science magazine).
You are less likely to be familiar with the periodical table table. A company called Levenger offers it for sale. The periodical table table is a storage and display receptacle for magazines and other periodical publications. (Thanks to investigator Thomas Michel for bringing it to our attention.)