One day, in line at the company cafeteria, Joe said to Mike behind him, "My elbow hurts like hell. I guess I'd better see a doctor"
"listen, you don't have to spend that kind of money" Mike replied. "There's a diagnostic computer down at Walmart. Just give it a urine sample and the computer will tell you what's wrong and what do to about it. It takes about ten seconds and costs only 10 bucks - A lot cheaper than a doctor"

So, Joe collected a urine sample in a small jar and took it to Walmart.
After depositing the ten dollars, the computer asked for the urine sample. He poured the sample into the slot and waited.
About 25 seconds later, the computer become quiet and the printer started.

Joe picked up the printout and read:
 You have tennis elbow.
  Soak your arm in warm water and avoid heavy activity.
  It will improve in two weeks.

Thank you for shopping at Walmart.

That evening, while thinking about how amazing this new technology was
Joe began wondering if the computer could be fooled.

He mixed some tap water, a stool sample from his dog, urine samples from his wife and daughter, and a personal sperm sample for good measure.
He hurried back to Walmart, eager to test the new technology. He deposited ten dollars, poured in his concoction, and awaited the results.

within 30 seconds, the computer produced the following results:

1. Your tap water is too hard. Get a water softener.  (Aisle9)
2. Your dog has ringworm. Bathe him with anti-fungal shampoo.  (Aisle7)
3. Your daughter has a cocaine habit. get her into rehab.
4. Your wife is gregnant. Twins... they aren't yours. get a lauyer.
5. If you don't stop playing with yourself, your elbow will never get better.

  Thank you for shopping at Walmart