Pipe some input to and set sail! UPDATE: Now works on MacOS (tested with iTerm) and no longer clutters terminal history! :D

set_sail.sh

#!/bin/bash

# Name:		set_sail
#
# Description:	This is a little script to make terminal output less dull.
#		Just direct stuff into the scripts stdin and you'll set sail!
#		Output can be slowed by passing --slow or -s as the first argument, you can also,
#		optionally, specify how long to wait between outputs if using the slow options.
#
# Example use:	cat <some_file> | set_sail --slow 1
#		apt-get update | set_sail
#
# Author:	Alexander Meuer | AlexMeuer.github.io

# Define colours!
SPEECH="\033[92m"
SHIP="\033[33m"
HORIZON="\033[36m"
WATER="\033[34m"
DEFAULT="\033[39m"

ERASE_LINE="\033[2K"

# See if the user wants to slow down the output.
if [[ "$1" == "-s" || "$1" == "--slow" ]]; then
  SLOW=true
  if [[ -n "$2" ]] && [[ $2 -gt 0 ]]; then
    SLEEP_TIME=$2;
  else
    SLEEP_TIME=0.5
  fi
else
  SLOW=false
fi

# Draws the greeting and the ship, with colours. Also draws the water that touches the ship.
drawShip() {
  echo 
  echo -e "${ERASE_LINE}${SPEECH}   ${GREETING}"
  echo 
  echo 
  echo -e "${SHIP}              |    |    |"
  echo  "             )_)  )_)  )_)"
  echo  "            )___))___))___)"
  echo  "           )____)____)_____)\\"
  echo "         _____|____|____|____\\\__"
  echo -e "${HORIZON}---------${SHIP}\\                   /${HORIZON}---------"
  echo -e "${WATER}  ^^ ^ ^^^^^^^^^^^^^^^^^^^^^^"
}

# Draws the water, moving the "waves" back as the ship sails onward unto adventure.
COUNTER_START=6
COUNTER=$COUNTER_START
drawWater() {
  echo -en "${ERASE_LINE}${WATER}"
  INDEX=0
  while [ $INDEX -lt $COUNTER ]; do
    echo -n " "
    let INDEX=$INDEX+1
  done
  echo "^^^^      ^^^^     ^^^    ^^"

  echo -ne "${ERASE_LINE}"
  INDEX=0
  while [ $INDEX -lt $COUNTER ]; do
    echo -n " "
    let INDEX=$INDEX+1
  done
  echo "     ^^^^      ^^^"

  if [ $COUNTER -eq 0 ]; then
    COUNTER=${COUNTER_START}
  else
    let COUNTER=$COUNTER-1
  fi
}

drawAll() {
  GREETING=${line}
  drawShip
  drawWater
  if $SLOW; then
    sleep $SLEEP_TIME
  fi
}

if read line; then
  drawAll
fi

# Read stdin, update the greeting text and redraw everything.
while read line; do
  echo -en "\033[13A" # Jump back up the 13 lines we printed
  drawAll
done < /dev/stdin