If you are familiar with Google Maps (http://maps.google.com/), I don't have to explain to you what MSN Virtual Earth (http://virtualearth.msn.com/) is all about. For those who are new to the whole mapping thing: MSN Virtual Earth combines mapping and local search to put the answers to your search questions in a geographical context.

I found the aerial/satellite imagery inferior to Google Maps. Still, give it a spin, it is a lot of fun to pan/zoom around the US!