While on call, radiology residents review imaging studies and issue preliminary reports to referring clinicians. In the absence of an integrated reporting system at the training sites of the authors' institution, residents were typing and faxing preliminary reports. To partially automate the on-call resident workflow, a Web-based system for resident reporting was developed by using the free open-source xAMP Web application framework and an open-source DICOM (Digital Imaging and Communications in Medicine) software toolkit, with the goals of reducing errors and lowering barriers to education. This reporting system integrates with the picture archiving and communication system to display a worklist of studies. Patient data are automatically entered in the preliminary report to prevent identification errors and simplify the report creation process. When the final report for a resident's on-call study is available, the reporting system queries the report broker for the final report, and then displays the preliminary report side by side with the final report, thus simplifying the review process and encouraging review of all of the resident's reports. The xAMP Web application framework should be considered for development of radiology department informatics projects owing to its zero cost, minimal hardware requirements, ease of programming, and large support community.