Traffic information MashUp
Click here to play with the Traffic Information MashUP - and here to find out what a MashUP is! In layman's terms a MashUp is where you (as an application developer) build upon an existing application - the term comes from DJ's mixing music samples.
Try rolling your mouse wheel to zoom right in and then right out to see just what's possible.
The application itself is interesting to me as it's using ATLAS (no punn intended) / Asynchronous JavaScript And XML (AJAX) which enables it to function like a "thick" application (one that's installed locally) though it's actually all hosted in the browser. You can drag the map around with the mouse and yet it doesn't flicker and updates rapidly.