Years ago, I was at our neighborhood Wal-Greens buying a can of baby formula and a bottle of Tylenol. I was a few dollars short, so I told the clerk to take the Tylenol off. The man behind me stepped forward and said, "No, don't." He paid for both items and then gave me a $20. He was gone before I could properly thank him. I was so moved I couldn't stop crying. Now, I step in whenever I can to help someone in the same situation.