LeMill is a web community for finding, authoring, and sharing open and free learning resources. It was developed as an open source server software in the EU 6FP CALIBRATE project. In LeMill, learning resources include content like media pieces and references, as well as activities, methods, tools, collections, and teaching/learning stories. Users can link to others by location, skills, and interests, and collaborate by joining groups and forums. All resources created in LeMill are published under a Creative Commons license to encourage sharing, reusing, and remixing of learning materials.