A network media player enables user-controlled playback of video or other content from various sources according to a playback control record. The network media player includes a content input port, an output port, and a processor configured to retrieve input content from one or more sources using the content input port. The processor is also configured to generate output content from the retrieved input content according to a playback control record so as to vary the playback of the retrieved input content. The processor is also configured to output the generated output content to the output port. In some embodiments, the playback control record includes an applicability identifier usable to determine whether the playback control record is applicable to input content and a content variation descriptor that defines an alteration to be applied to the retrieved input content.