"A man goes to the doctor's for his wife's test results: Mr Smith: "I'm here for Mrs Smith's test results . Receptionist: " Oh I'm sorry Mr Smith, there's been a problem, we have 2 sets of test results for a Mrs Smith and we don't know which belongs to your wife. I'm afraid it's bad news or terrible news. One test shows Alzheimer's Disease, the other shows AIDS . " Mr Smith: " That's awful! What should I do" Receptionist: "The doctor suggests you drop her off in the middle of town . If she finds her way home, don't shag her"."