This thread reminds me of my brother's stories from working at UPS during the summer. Apparently, the supervisors would check each truck to see that the packages were loaded properly and neatly. My brother was paired with a guy who had a method for neatness. He would start by making a neat wall of boxes on the back end of the truck. He'd leave one corner open and then proceed to launch every package through the hole. When he was done, he'd fill the gap with a few boxes, and voila, a neatly loaded truck.
Also, from talking to USPS and UPS people, I would advise against marking packages "fragile." Apparently, many workers take offense that someone should think their package to be more important than others.