Visualize the Return Code of Your Last Command via the Prompt

I like to have a pretty obvious indication of the success of failure of any commands I might have run. To accomplish this I add several color coding shortcuts to my .bash_profile:

RED='\033[0;31m'
GREEN='\033[0;32m'
BLUE='\033[0;34m'
NOFORMAT='\033[m'

#return code visualization
RVAL='$(RET=$?; if [ $RET -eq 0 ]; then echo -ne "$GREEN"; else echo -ne "$RED"; fi; echo -ne "$RET")'

Using those I can make a relatively simple $PS1 that I add to the end of my .bash_profile:

# prompt
export PS1="$BLUE\t $NOFORMAT\h $BLUE\w $RVAL\r\n\\\$ "

That gives me a prompt that looks like this for root after a successful command:

11:57:24 MyBox /etc 0
#

or like this for a normal user after a failed command (CTRL-C in this case):

11:57:27 MyBox ~/git 0
$

I personally don't put any color changes after the newline \n. It tends to lead to funky things when scrolling through your history or dealing with really long commands.