In this article, we show that decentralized virtual currencies can be powerful tools for societal transformation. Indeed, the study of the joint and disjoint elements between the first Bitcoin currencies, SELs and local currencies, reveals that these projects are not so far. Then, we present the current evolution of crypto-currencies towards new energy aware, community-based, useful and fundamentally innovative protocols, emphazing their strong potential. Finally, some recent crypto-currencies are close to the values of the Social and Solidarity Economy, and even though they have some technical and theoretical problems, they have the merit of offering new perspectives. Finally, we propose an idea of decentralized money geolocalized melty, which would allow us to meet a certain number of limits that are experienced by traditional local currencies.