From Steven Garrity at Acts of Volition, The Sound of Data, where he takes data and pipes it out to an audio output -- just to, uh, you know, to hear what it sounds like:

Spurred on by a recent weekend full of hot-tub induced dehydration, beer, and lack of sleep, some friends of mine discovered an interesting (I think, I at least) capability of the command line computer interface. Prepare to be really geeked-out.

As I wrote briefly about last year, on the Linux command line, you can pass the output of one program into another by joining them together with | (the "pipe" character).

...

It occurred to one of us, in our sleep-deprived state, that you might be able to pipe the output of the random number generator into an audio player, and hear random noise. So, we tried this:

cat /dev/urandom | aplay

Most of it is much as expected -- white noise from random data, the self simularity and repetition of file systems. The coolest example, tho', is the American flag -- which sounds like a strange techno-dance thing. A faint, frantic pulse under a dial-tone like high pitch, and a field of ascendent scales.