This volume includes the social and technical research performed in the past three years on Commoncoin, the digital complementary currency for Commonfare. The research comprised a design exercise for Commoncoin and a technical implementation, the Social Wallet API. This two elements have been tested with two real world communities with Commoncoin as a currency for the occupied cultural centre Macao in Milan in 2017 and Santacoin as the currency for the biggest performative art street theatre festival in Italy, the Santarcangelo Festival in 2018. The conclusion is that both design and technical components coupled with the real world tests made emerge the need to further experiment with new forms of re-appropriation of the power of money by and for the users of money systems.