Obligatory Google BBS reply: Now the whole script of how it would connect comes from a viral video by Squirrel-Monkey.com (see also the link at the page). "Google BBS" just put this into interactive reality. On the sound: This is not a technical feature of the modem, but you would have actually a modem-script to switch it to mute. (The usual configuration was: I want to here the handshake sequence, but as soon as the connection stands, mute. But this was actually scripted behavior. You could have it all mute or monitor sound all the time. There are two distinctive sounds and the second one – reconnecting & fetching more data – isn't a handshake sound.)

@sdfjkl - I found the joke on GOOGLE.COM and the typo actually funny in the original video and wouldn't have wanted to miss it in the application.