Modems have been around for a very long time. By the time the mid-80's rolled around, a 300-baud cuff modem was well within the range of a young kid who had some paper-route money, because that's what I did. And my family was not wealthy at all.
[edit]- I found an article from 1987 talking about how amazingly fast (and cheap) the new 2400 baud modems were. I had to chuckle, as I still remember going from 300 (slow enough that your reading speed was baud-limited) to 1200 (wow! I can barely keep up!) 2400 and above was a speed that seemed almost decadent.