Metadata for the World Wide Web is important, but metadata for peer-to-peer networks is absolutely crucial. In this talk I will give an overview of the open source project Edutella and related projects, which combine semantic web and P2P technologies in order to make distributed repositories possible and useful. I will start by describing the main services of the Edutella network infrastructure and its architecture based on the exchange of RDF metadata, starting with the query service as one of the core services of Edutella. I will then describe efficient P2P routing topologies which minimize traffic and distance between the peers, and discuss their properties and characteristics. Furthermore, I will show how they can be used as super-peer backbones for schema-based P2P networks. Finally, I discuss two application of the Edutella network, the first one for digital libraries (OAI-P2P), the second one for distributed learning management systems in the context of the EU/IST project ELENA.