One artifact from my childhood in the 1960's that I still remember vividly is the series of plastic sliding block puzzles manuafactured by The Roalex Company of Forest Hills, NY (no relation to the maker of fine timepieces).
"Vintage Plastic Sliding-letter Puzzles,"
Word Ways: Vol. 44
, Article 22.
Available at: http://digitalcommons.butler.edu/wordways/vol44/iss4/22