So you've Googled Earth, the Moon and your local area. Now try Google Mars. Released yesterday, this latest site from the internet search giant, allows you to 'surf' Mars and find sites of interest, such as Mars landers, using the same interface as you may have used in Google Maps to find local facilities in your area.
A nice feature is the ability to switch between an elevation map (generated from Mars Orbiter Laser Altimeter data), visible or infrared views. Unfortunately the highest resolution images from Mars Express are not used, but there are some higher resolution pictures of landing sites etc.