CompuServe of course used the XXXXX,XXXX octal usernames, and you could append @compuserve.com for a valid email address, but later we could choose a vanity email (first come, first served), e.g., something@compuserve.com. Then later they offered @csi.com addresses. POP3 access to your CS mailbox was eventually an option, as well.<p>For a long time (maybe still?) you could access a terminal version of the CS interface over telnet. Basically all the same features as the GUI application, just in text.<p>There was also the original Microsoft Network (later shortened to MSN), which included a bunch of communities and boards. It was a Windows 95 application, and went through a semi-public beta then eventual release in parallel with the OS. You could connect through dial up or over the Internet, if I recall. I remember being impressed I could open two boards at the same time, unlike CS.