From http://www.last-outpost.com/~malakai/weather/index.html:[The "Which Host?" prompt was from the Hermes service (terminal to host service) of the Merit Network. One could get to the MTS systems at UM and WSU from "Which Host?", but the prompt was not part of or provided by MTS. MTS did run the Merit "Host locator" service for the Merit Network. The "Host locator" was a bit like the Internet's Domain Name System (DNS), certainly not as large or as distributed, but in some ways more flexible. -Jeff Ogden 16 July 2014]
I was at The University of Michigan in the early 90's getting my computer science degree, and was lucky enough to have been a user of The Michigan Terminal System in the last years of its life. Believe it or not, there was a network before "The Web", and back then two very cool places that the "Which Host?" prompt could take you were The Last Outpost , a multi-user "Dungeons and Dragons" text adventure game, and a weather service called "um-weather". Surprisingly, both of the services continue to run today, nearly 15 years later. As you may have guessed from the banner on this page, I run The Last Outpost. UM-Weather, which was run by a another UM student, Jeff Masters, went on to become The Weather Underground , the most comprehensive weather site on the 'net.