A useful little bashrc addition

I really like checking if commands have executed successfully. This is something quite important if you are administering a machine. Normally I just echo $? but now I have added a new line to my .bashrc that will show me this in colour.

export PS1='\[\033[0;32m\]\u@\h \[\033[0;33m\]\w\[\033[${?/[^0]/31}m\]\$ \[\033[0;38m\]'

This will make the prompt green if everything went OK and red if the process didn't return 0. Nice little helper :)