A handy wikipage on the Archlinux wiki giving a good overview of how to change the colour of your command prompt. I changed ours to differentiate between development and production because otherwise I'd forget! Also changed it to highlight the host I'm on which is very helpful too.

linux_command_prompt

So get imaginative!

(side note, all of my development servers are named after fruits in the drupe family, so I have nectarine, cherry, apricot, peach and mango so far!)