I played it a few times on terminals, with no real
idea of what (or WHO)
 was at the other end of the connection.
 (Isn't that the "reverse Turing Test"?  where you see whether a human can
 convince the party at the other end of the line that it is a machine?) 
    Unrelated piece of fun info:
    Sunday I went to a local motel with my girlfriend (I'm hosting two
ladies on my home and primitive noises may not be too comfortable for them).
When we were checking out, there was a monitor on the out with your bill
and...wow, it was a terminal, connected to some kind of *nix system,
everything was serial-based!!! I felt myself in 1980!!! :oD
    Very interesting view :D