Mike Krieger at Z-D and I have had a series of amusing emails recalling all the various email systems down through the years that we have known, used, and abused. He goes back to the dawn of connected email with IBM mainframe systems PROFS and DISOSS. When I was first living in LA, Mike was an SE for IBM midrange systems and we both used these beasts.

Here are a few other systems to jog your memories this morning:

Easymail (AT&T)
MCImail
Radiomail (precursor to BlackBerries)
The Source
CompuServ
Prodigy
AOL
Higgins
cc:mail
Fidonet

Not to mention all the various BBS’s that were floating around back then. And speaking of BBS, you might want to take a look at this movie here.