Prodigy
In the early Nineties my family had one computer, a Zeos 386, and Prodigy was my very first experience with anything resembling the internet, including e-mail. I spent a lot of online time playing this labyrinth game called Mad Maze, which you can once again play in its entirety, as long as you use Internet Explorer.
Mad Maze is being discussed at:
and on these blogs: