To make use of or exploit something to one's advantage to the furthest possible extent. He's been milking the bit of celebrity his book brought for all it's worth, but if he doesn't write something new soon, he'll just fade away as another has-been. The woman's admission of misremembering part of her testimony has given the company new ammunition in its defense, and they are milking it for all it's worth. He's been milking his back injury for all it's worth lately to get out of doing any heavy lifting around the warehouse.