In this paper, we describe the SomeWhere semantic peer-to-peer data management system that promotes a “small is beautiful” vision of the Semantic Web based on simple personalized ontologies (e.g., taxonomies of classes) but which are distributed at a large scale. In this vision of the Semantic Web, no user imposes to others his own ontology. Logical mappings between ontologies make possible the creation of a web of people in which personalized semantic marking up of data cohabits nicely with a collaborative exchange of data. In this view, the Web is a huge peer-to-peer data management system based on simple distributed ontologies and mappings.