Any data collection or processing activity that incurs significant risk requires a Data Protection Impact Assessment (dpia), which is a comprehensive, analytical evaluation of the risks of violating fundamental data protection rights. While performing a dpia is considered a cornerstone activity for demonstrating gdpr compliance and adherence to data protection by design principles, they are rarely made public by organizations. Although dpias have received considerable attention from a wide range of inter-disciplinary research perspectives, this attention remains fragmented and a solid comparative basis does not yet exist. In this paper, we present our efforts in establishing an open repository that indexes common and representative dpias. Starting from clearly-defined inclusion requirements for representative cases, we present the outcome of the first two years of consolidation efforts: a repository indexing 130 dpias. Finally, we discuss how this repository enables interdisciplinary dpia research, on comparing and evaluating diverse dpia approaches, models, and tools. The resulting repository is a valuable resource for researchers across disciplines, to spark debate on dpia goals andquality, and to evaluate different dpia methodologies, approaches, and tools.