Linux terminal clock

small

while true; do clear; date +"%H : %M : %S"; sleep 1; done

big

package figlet required

case 1

while true; do tput clear; date +"%H  %M  %S" | figlet -t -c -f mad_nurs; sleep 1; done

case 2

while true; do tput clear; date +"%H  %M  %S" | figlet -t -c -f fraktur; sleep 1; done