The Sky Hook allows for its center of gravity to be manipulated by the addition of weight to the hooked end. Once you know the secret, you can easily balance it on the tip of your finger... or on the end of a pencil... or even on the tip of your nose!
Balancing toys were popular in the 19th century. Dating back to ancient China and India, where they were most often carved from soft wood, the western balancing toys were traditionally made from tin or metal. Illustrations of balancing toys can be found in educational literature from the 18th century. The physics governing the movement of such toys intrigued and amazed people.
The Sky hook pictured is made of plywood 3/8” thick, however I have made some in the past from heavy cardboard and they work just as well.