NewYorkCoin is a clone of Dogecoin that was established in March 2014. The coin has gone through a revival after dormancy of development starting in January 2018. It is a retail focused cryptocurrency.
The main goal of Callisto is to research and develop a reference implementation of a self-sustaining, self-governed, self-funded blockchain ecosystem and development environment. Callisto aims to establish a secure and contribution-friendly environment for further protocol development and improvements. It will rely on a built-in system of smart-contracts to achieve this goal.