I love crap like this. This was done as a (very capable) demonstration that the physical/datalink and network/transport layers of the TCP/IP stack are completely seperable. Read all about it.
“After typing the ping command, Danny tapped smartly on the enter key, and a hush fell upon the room as the students waited to see what would happen. There was a short pause, and then suddenly the primitive sounds of a message being beaten out on a set of bongos filled the air.”
Via Boing Boing.