We will very briefly introduce Beernet's architecture describing the peer-to-peer network topology, the distributed hash table, and the transactional layer for replicated storage (called Trappist). We will also describe Beernet's API to create peers, exchange information between them, and to store and retrieve data from them. We will finally describe some applications built on top of Beernet, such as a small wiki, a collaborative drawing tool, and a web-base recommendation system. Beernet is a library to build distributed systems as peer-to-peer networks. It provides replicated storage with distributed transactions, which are highly robust because they do not rely on a centralized point of control. Beernet can be used to develop synchronous and asynchronous collaborative applications. We have used it to build a decentralized wiki, a collaborative drawing application with gPhone clients, and a web-base recommendation system. Beernet stands for pbeer-to-pbeer network, where words peer and beer are mixed to emphasise the fact that this is peer-to-peer built on top of a relaxed-ring topology (beers are a known mean to achieve relaxation). The relaxed-ring provides a distributed hash table (DHT) with no central point of control and without relying on transitive connectivity between peers.