Google Earth's Forgotten Forerunner, Microsoft TerraServer
I actually recall seeing and using Microsoft TerraServer, and am disappointed that I forgot all about it until I read "Microsoft Invented Google Earth in the 90s Then Totally Blew It". TerraServer was remarkably Google Earth-like, but Microsoft seemed to consider it more of a technical proof of concept than any kind of viable product at the time.
Terraserver could have, should have been a product that ensured Microsoft would remain the world’s most important internet company well into the 21st century. It was the first-ever publicly available interactive satellite map of the world. The world’s first-ever terabyte-sized database.