Ususally used in an office environment, this term describes when there are not many teabags left so it is prudent to use 1 teabag for an entire round of teas to make the remaining bags last as long as possible. So named due to the reluctance to shell out for a new pack of tea due to the global credit crunch.
Paul: Justin are you making the teas then?
Justin: Sure... Only 3 bags left so is everyone up for a credit crunch tea?
Paul: Yeah go on then.