Facet browsing has become popular as a user-friendly interface to explore data repositories. In this work, the authors apply the Linked Data Design Issues to explore, visualize and use information that is semantically related to open educational resources that are shared via the OpenCourseWare Consortium and OCW Universia.net, two communities of over 280 member institutions worldwide committed to sharing their courses and OER online. Linked data have the potential of create bridges between OCW data silos. To assess the impact of Linked Data in OpenCourseWare, the authors present a faceted tool called Serendipity and a Data Visualization Web interface called Serendipity Maps. Serendipity is an interface of faceted search for open educational content based on Open Educational Resources Data. Additionally, the linked OER and OCW data environment enabled us to show data visualizations.