Online social networks have become essential for many users in their daily communication. Through a combination of the online social networks with opportunistic networks, a new concept arises: Local Social Networks. The target of local social networks is to promote social networking benefits in physical environment in order to leverage personal affinities in the users' surroundings. The purpose of this paper is to present and discuss the concept of local social networks as a new social communication system. Particularly, the preliminary architecture and the prototype of local social networks are presented as well as possible privacy concerns are identified and discussed. In order to address the arising privacy issues, a new concept called diverged personalities is introduced. This concept is based on presentation of different personalities of the user in different circumstances.