Milking the cow can be used to describe attaining the absolute most from any given situation.
Sometimes called 'milking the cash cow', 'milking the cow' can also be applied to any franchises which continue to drain the public of as much cash as possible and attempt to attach the brand name to absolutely everything, be it cereal, video games, car adverts, tshirts, bedsheets, plush toys, action figures, computer accessories or anything else that would be seemingly unrelated.