A rather amazing feat of electromagnetics...
This program is based on "Tempest" attack, aka Van Eck Phreaking. In short, all electric devices send out amounts of electromagnetic radiation - computers are good at this, of course. With proper receiver, you can, for instance, take the electromagnetic interference generated by your neighbor's computer monitor and transform it back into the image.
Tempest for Eliza is a program (needs SDL and some luck to compile) that takes advantage of this. Basically, it runs in full screen mode and generates a pattern on screen that will generate specific kind of interference on desired part of electromagnetic spectrum (only AM radio currently supported - what did you expect, gamma rays?). Place an AM radio receiver near the screen, tune it to that frequency, and you should hear a sound. What sound, that is decided by the program.
In other words: It turns your monitor into a (very low-powered) AM radio transmitter!
TfE can play simple music files. It can also play MP3 files (with the help of external programs).
Icecast is for wimps. =)
Home page: http://www.erikyyy.de/tempest/