So the other day Im walking up to a house to make a delivery. The customer had the stereo going, so he never heard me pull up. I smell weed through the open window, and can hear the unmistakeable sound of a bong hit in progress. So I wait...and wait...and wait...until I hear his thumb let up off the carb hole, then I POUND on the door and announce "UPS" in a deep voice. My timing was perfect; I scared the crap out of the poor guy right at the EXACT moment when his lungs were maxed out. This sent him into an uncontrollable fit of spastic, hacking coughing. I could see him through the window, his eyes were watering, he had snot running out of his nose, and in his panic he knocked his bong off of the coffee table and spilled weed and bong water all over the floor. His friend was jumping around trying to hide everything. It was priceless. When he finally made it to the door I very politely gave him his package, but while he was signing the DIAD I kept sniffing the air and looking around with a suspicious look on my face like I smelled something funny. I'm betting he was paranoid for the rest of the day!!