Released in the mid-1960s, the Cracker Jack Encyclopedia gets our "thumbs up" for its sheer uniqueness. Consisting of twenty miniature books with actual content that can be read, they are hard-to-find but worth finding and in their entirety is a thing of art.
Each Cracker Jack Encyclopedia book or volume covers a different topic. Though aimed for the younger set, the topics range from birds to famous women and men to unusual flowers and plants. The books measure 1.25" in width by 1.75" in height with book covers made of cardstock or thin cardboard. Each has about ten pages that were made of cheap newsprint paper with inexpensive glue used to bind the book pages.