GNU social (previously known as StatusNet and once known as Laconica) is a free and open source software microblogging server written in PHP that implements the OStatus standard for interoperation between installations. While offering functionality similar to Twitter, GNU social seeks to provide the potential for open, inter-service and distributed communications between microblogging communities. Enterprises and individuals can install and control their own services and data. GNU social has been deployed on hundreds of interoperating servers.
gnu social seems to be a 100% trade-free social network for anyone. You can register an account and then use it, without trading your data, attention, money or anything else.