my colored prompt on black terminals:
PS1='\[\033[0;31m\]${debian_chroot:+($debian_chroot)}\u\[\033[1;31m\]@\[\033[0;31m\]\h\[\033[1;33m\][\t]\[\033[1;35m\]\w\n\[\033[1;32m\]\$ >\[\033[1;37m\]'
username@hostname[time]currentpath $ >
place with „export“ in ~/.bashrc (if bash is your shell)
edit 2017: have a look at liquidprompt