I have been hooked on the http://maps.google.com/ since it was launched a few months ago. Now you even have the option to get satellite images in addition to the very nice maps.
Google Map with satellite image showing my office as well as the famous Marin Civic Center by architect Frank Lloyd Wright.
You can even pan and zoom satellite images from around the world. This technology was formerly by Keyhole Corp. and cost $29.95 but Google aquired them 6 months ago and it is now free.