###############
for i in {1..60}; do echo -en "#"; sleep 1; done

[=======>   ]
for i in {1..10}; do l=$((10-$i)); printf "[%${i}s"|sed 's/ /=/g'; printf ">%${l}s]\r"; sleep 1; done
for i in {1..10}; do l=$((10-$i)); printf "[%${i}s"|sed 's/ /=/g'; printf ">%${l}s]\r"; sleep 1; done; printf "[%${i}s"|sed 's/ /=/g'; printf ">%${l}s]\n"

Countdown 10..0
for i in {10..0}; do echo -ne "  $i\033[0K\r"; sleep 1; done

rotate / --> | / - \ ...
while true; do sleep 0.25 && echo -ne "\r\\" && sleep 0.25 && echo -ne "\r|" && sleep 0.25 && echo -ne "\r/" && sleep 0.25 && echo -ne "\r-"; done