Is it possible to change the background color of Terminal.app from the shell? If so, how?
I don't know the specifics, but I imagine you'd want to write an AppleScript program which you invoke from your shell script. The AppleScript would "Tell" Terminal to change its background colour.
osascript -e "tell application \"Terminal\" to set background color of window 1 to {0,45000,0,0}"
(Can't take the credit)