This is exceedingly cool. If someone wants to play with lower bandwidth data (text, basic file transfer) over sound, it's a pretty active area in the world of

This is exceedingly cool. If someone wants to play with lower bandwidth data (text, basic file transfer) over sound, it's a pretty active area in the world of amateur radio. You can download the open-source program fldigi (http://www.w1hkj.com/modes/index.htm http://www.w1hkj.com/modes/index.htm) on 2 computers, point speakers and microphones at each other, and try sending text (or files/images). The "flmsg" program will send pre-formatted stanzas which get converted into standard forms. That being said, doing things like TCP/IP and other data is rather difficult on radio, mainly due to the duplex requirements and frequency spacing. But in pure audio, much more possible.