Obtain live video streams and show them in your app. Access the streaming servers to locate those broadcasting on Yahoo! Live, and see data about the streams, such as the broadcaster and viewers. Those with webcams can be part of the broadcast as coviewers, so you can programmatically access coviewer data, too.
In the past two weeks, video related mashups have been the largest category of new mashups added to the ProgrammableWeb mashups catalog. In the two weeks ending on July 6, 25% of new mashups were in the video category.