The SIMILE project is based at Massachusetts Institute of Technology and one of their developments are interactive timelines that you can use to visualise time based events.
This can be used to display historical events. In this example they've displayed the events surrounding the assasination of JFK, and if you have time to play with the code you can create your own variations.
Meg found a web service that uses this technology to help you easily create a timeline for your own web site. The 'My Timelines' service just uses the RSS feed from your web site and supplies you with the code to place a timeline on your own web site. Meg has created one for Cakes, and it allows you to easily view activity on the blog.
It could prove to be a good way of introducing the concept of RSS feeds to people, because it demonstrates how they work in a visual way.