[mmphosis]

Here's a snippet from my bash_aliases ...

  ### PROMPT ###
  
  function user_host_pwd() {
      printf "%c " '-'
      user -n
      printf "%c" '@'
      violet
      printf "%s" "${HOSTNAME%%.*}"
      normal
      printf "%c" ':'
      path "${PWD}"
  }
  -() { user_host_pwd ; }
  prompt_command() {
      local current="$USER@$HOSTNAME:$PWD"
      local last_cmd
      if [ "$current" == "$USER_HOSTNAME_PWD" ]; then
          last_cmd="#$(history | tail -n 1 | sed -e 's/.*[0-9]  //' | cut -d ' ' -f 1)"
          for cmd in $COMMANDS_USER_HOST_PWD_PROMPT
          do
              if [ "#${cmd}" == "$last_cmd" ]; then
                  USER_HOSTNAME_PWD=""
                  break
              fi
          done
      fi
      if [ "$current" != "$USER_HOSTNAME_PWD" ]; then
          export USER_HOSTNAME_PWD="$current"
          user_host_pwd
      fi
  }
  COMMANDS_USER_HOST_PWD_PROMPT="cd ssh sudo su login $(sed -e '/^#.*$/d' -e '/^$/d' -e 's@^.*/@@' /etc/shells | uniq | xargs)"
  PROMPT_COMMAND=prompt_command
  PS1='$ '
  [ "`id -u`" -eq 0 ] && PS1='# '