This slick little project baked at MIT yields a really robust interactive timeline via AJAX. A demo for the timeline can be found here. As you can see it allows for multiple points within the timeline with pop-up tool tips that give more information about each point. By using your scroll wheel on your mouse you can scroll back and forth through the timeline.
They’re are easy to follow tutorials on how to install the widget, so installation should be easy. The getting started tutorial is very easy to understand. It gives examples on how to connect to the API and shows you how to get your own timeline up and running in no time. Their are more advanced tutorials what will show you how to change the look and behavior of the timeline.