A knowledge base allows a user to catalogue and search a collection of knowledge they have accumulated. A social knowledge base is a knowledge base where one's collection of knowledge can be shared with one's peers. We created a design for a social knowledge base by combining technologies from several research areas including semantic overlay networks, phrase embedding, peer-to-peer (P2P) identity, and distributed search. In particular we explore how trust in the knowledgeability of peers (a.k.a. reputation) can be established and used for different (potentially overlapping) domains of knowledge/expertise. This design was partially implemented, and was evaluated as a proof of concept.