I recently happened upon this intriguing little API that provides a nice interface for displaying events on a timeline. It was pretty easy to get my head around it and it's pretty easy to setup and use. It's got a Google Maps-like scrolling interface...
Yahoo! has released an API that allow you to easily embed a media play that will automatically attach itself to MP3 links. They had one that just linked to their own music library, but that's boring. Here is a sample HTML page that has some MP3 links...