Today, new digital platforms for sharing, swapping and other ways of collaborative consumption are widely associated with positive economic, ecological and social effects. At the same time, existing platforms like Airbnb and Uber are increasingly criticized in public debate for having negative effects on people, local economies and our planet. As a counter model, new decentral models combining alternative organizational forms (such as platform cooperatives) and new technologies (such as Blockchain technology) are discussed and tested. These and other alternative models promise to better reach social-ecological goals and offer potential to transform the sharing and platform economy.