Polyorama: Endless Landscape.

From Grand Illusions toy shop:

The Polyorama originally dates from the mid 18th century, and consists of a series of illustrated cards which combine to form an ‘endless landscape’ – you can place the cards in any order, and the pictures will still fit together to create a landscape.

16 cards means that there are factorial 16 possibilities, i.e. 20,922,789,888,000 different pictures that can be made.

I guess this passes for "fun" in the 18th century! Link