#!/bin/env bash
echo "What music to play?"
echo "[1] Groovy; blues"
echo "[2] Japanese"
echo "[3] ??"
echo "[4] 8 bit Bass boosted"
read music

if [[ $music -eq 1 ]]; then
    echo "Enjoy!!"
    cat /dev/urandom | hexdump -v -e '/1 "%u\n"' | awk '{ split("0,3,5,6,7,10,12",a,","); for (i = 0; i < 1; i+= 0.0001) printf("%08X\n", 100*sin(1382*exp((a[$1 % 8]/12)*log(2))*i)) }' | xxd -r -p | pacat --channels 2 --format S32 --rate 24000
fi


if [[ $music -eq 2 ]]; then
    echo 'Enjoy!!'
    cat /dev/urandom | hexdump -v -e '/1 "%u\n"' | awk '{ split("4,5,7,11",a,","); for (i = 0; i < 1; i+= 0.0001) printf("%08X\n", 100*sin(1046*exp((a[$1 % 8]/12)*log(2))*i)) }' | xxd -r -p | pacat --channels 2 --format S32 --rate 24000 &

    cat /dev/urandom | hexdump -v -e '/1 "%u\n"' | awk '{ split("0,2,4,5,7,9,11,12",a,","); for (i = 0; i < 1; i+= 0.0001) printf("%08X\n", 100*sin(1382*exp((a[$1 % 8]/12)*log(2))*i)) }' | xxd -r -p | pacat --channels 1 --format s32 --rate 2000
fi


[ $music -eq 4 ] && {
    cat /dev/urandom | hexdump -v -e '/1 "%u\n"' | awk '{ split("4,5,7,11",a,","); for (i = 0; i < 1; i+= 0.0001) printf("%08X\n", 100*sin(1046*exp((a[$1 % 8]/12)*log(2))*i)) }' | xxd -r -p | pacat --channels 1 --format S16 --rate 80000 &

    cat /dev/urandom | hexdump -v -e '/1 "%u\n"' | awk '{ split("0,2,4,5,7,9,11,12",a,","); for (i = 0; i < 1; i+= 0.0001) printf("%08X\n", 100*sin(1382*exp((a[$1 % 8]/12)*log(2))*i)) }' | xxd -r -p | pacat --channels 1 --format u8 --rate 8000 --volume=50000
}


if [[ $music -eq 3 ]]; then
  echo "Taken from r/coding; enjoy!!"
  awk 'function wl() {
        rate=64000;
        return (rate/160)*(0.87055^(int(rand()*10)))};
    BEGIN {
        srand();
        wla=wl();
        while(1) {
            wlb=wla;
            wla=wl();
            if (wla==wlb)
                {wla*=2;};
            d=(rand()*10+5)*rate/4;
            a=b=0; c=128;
            ca=40/wla; cb=20/wlb;
            de=rate/10; di=0;
            for (i=0;i<d;i++) {
                a++; b++; di++; c+=ca+cb;
                if (a>wla)
                    {a=0; ca*=-1};
                if (b>wlb)
                    {b=0; cb*=-1};
                if (di>de)
                    {di=0; ca*=0.9; cb*=0.9};
                printf("%c",c)};
            c=int(c);
            while(c!=128) {
                c<128?c++:c--;
                printf("%c",c)};};}' | sox -t raw -r 64k -c 1 -e unsigned -b 8 - -d
fi
exit 0

Mine is basically the same, but since it pipes your filesystem layout into aplay instead of random bits, it’s not just brown noise.
It plays you the song of your system.
(also, it can damage your speakers, headphones and/or ears)