The next night, after his 4th beer, the doorbell rang. It was the cockroach again. This time, it punched Tom in the stomach, and walked away.
The next night Tom had only one beer. Then the doorbell rang. Tom slowly opened the door and saw the giant roach. It kneed him in the groin.
On the fourth night, Tom didn't drink any beer. But this time, the 6-foot roach arrived again and beat the living crap out of Tom.
The next day, Tom went to the doctor. "What can I do, Doc?," he asked.
The doctor replied, "There's nothing you CAN do. It's just a nasty bug that's going around."