This node was inspired by
"catting weird things to /dev/audio/"
I seem to remember that at one time (a long time ago) on SunOS 4 systems, the default permissions on /dev/audio were such that you could do something like this:
% rsh remotenode 'dd bs=1k if=/dev/audio' > /dev/audio
(Using dd rather than cat tends to smooth out problems introduced by network delays) This would essentially connect the microphone on the remote node to the speaker on the local node over the network, enabling you to eavesdrop on people near the remote node.
(not that I ever did that... well, ok, but all I ever heard was typing noises... )
Of course you could also scare the living shit out of people late at night by doing the converse:
% cat /dev/audio | rsh remotenode 'dd bs=1k of=/dev/audio'
And then you shout something rude into your microphone. Hilarity ensues.