The Highlights

• Dive beneath the water surface (videos are on some locations!)
  
• explore 3D underwater terrain and browse
  ocean-related content
  
• Historical
  Imagery (travel back in
  time through archival satellite and aerial imagery)
• Touring (create a narrated tour in &
  share it with the world)
• Google Mars 3D, which features hi-res
  imagery and terrain of the red planet

And if you have never heard of Google Earth, you need to crawl out from under your rock and plug-in to the net.

Get Google Earth Here

Happy virtual traveling!