On Ubuntu 10.10:

sound.c:

    #include <stdio.h>
    #include <math.h>

    int main()
    {
        int t;

        for ( t=0; ; t++ ) putchar( t*((t>>9|t>>13)&25&t>>6) );
    }

Then to compile and run:

    $ gcc sound.c && ./a.out | aplay -