worldclock.sh/worldclock.sh

#!/bin/bash
AS=🌏
EU=🌍
AM=🌎
NIGHT="🌙"

TZONES="America/Los_Angeles America/Denver America/New_York Europe/Amsterdam Asia/Tokyo Australia/Brisbane"
H=`TZ=Europe/Amsterdam date +%H`
if (test $H -gt 2 -a $H -lt 9); then
    WORLD=$AS
elif (test $H -gt 9 -a $H -lt 18); then
    WORLD=$EU
else
    WORLD=$AM
fi


function print_clock() {
    TZ=$1
    H=$(TZ=$1 date +%H)
    COLOR=""
    if (test $H -gt 8 -a $H -lt 18); then
        echo -n $WORLD
        COLOR="\033[1;33m"
    else
        echo -n $NIGHT
        COLOR="\033[1;34m"
    fi
    if (test $H -gt 5 -a $H -lt 9); then
       COLOR="\033[0;33m"
    fi

    if (test $H -gt 17 -a $H -lt 23); then
       COLOR="\033[0;36m"
    fi
    echo -ne "${COLOR}   $1\r\t\t\t\t: "
    TZ=$1 date -R
}

while (true); do
    clear
    for t in $TZONES; do 
        print_clock $t
    done
    sleep 61
done