We present an approach that uses social net- working and semantic web technology to share knowledge within the software engineering community. We propose to use existing Web 2.0 services such as social bookmarking and blogs as the infrastructure to share knowledge arte- facts. Due to the openness of these services, it is crucial to provide support in order to establish the trustworthiness of knowledge artefacts. The solution proposed is designed fol- lowing the original semantic web stack architecture[1] and uses existing and emerging W3C semantic web standards such as RDF [16], OWL[14], and SWRL[19]. The WebOf- Patterns [22] project is presented in a case study. This includes an Eclipse based WebOfPatterns client that can be used to discover design pattern definitions in social net- works, to define and publish patterns, to rate patterns, to establish the trustworthiness of patterns found, and finally to x-ray Java projects for instances of discovered patterns.