A sub-category of matryoshka collecting is the counting toy, which is usually many small pieces inside a larger doll, used to encourage children to learn to count and play. Sometimes the dolls become more elaborate and leave the playground and take on a life of their own. Banks are self-explanatory and can either open, or be unopenable. Many of these novelties come from Seemenov and Sergiev Posad.
All prices are in USD.