#!/bin/bash

echo -e "\nspongifying $@...\n\n"

str="$@"
lstr="${str,,}"
ustr="${str^^}"

# https://stackoverflow.com/a/10552175
for (( c=0; c<${#str}; c++ )); do
 # https://stackoverflow.com/a/1195035
 if [[ $((1 + $RANDOM % 10)) < 5 ]]; then
  echo -n "${lstr:$c:1}"
 else
  echo -n "${ustr:$c:1}"
 fi
done
echo; echo