1. The document describes a case study of using the microblogging platform cirip.eu to build personal learning environments (PLEs). 2. Key features of cirip.eu that support PLEs include public and private groups, importing messages from other social networks, multimedia embedding, and mobile access. 3. The authors analyze cirip.eu as a social network centered around user profiles and used to share learning objects, designs, and participate in groups. They provide an example of a group PLE conference on cirip.eu to facilitate communication and sharing in the domain of PLEs.