During a recent pub lunch, a couple at another table paid and left a $20 tip. Moments later, a breeze from a door opening sent the twenty dancing to the floor. Another customer, casually walking by, bent down and pocketed the cash. Found money! The server returned to the empty table, visibly upset at the lack of a tip. We considered speaking up, but weren't sure how it would play out. "Maybe we shouldn't tempt fate today? This is a problem for karma." So, we tipped that server an extra $20.