I too have used the hair dryer trick successfully. Regarding the tape residue, hold the removed sticker around the tip of your finger and tap it against the area where the residue is. You'll be surprised how it will remove the residue. If the old sticker 'runs out of stickum'; try a new label, just don't press it against the box quite as hard.
When it comes to removing clear or brown packing tape from that precious factory shipper, try removing that tape when the box is very cold. It seems to release quite easily and leaves the brown shipper pretty much intact. This trick works well for those of us in the northern climes, but others will have to become more inventive.
You might try the refrigerator or freezer - however, do this when the wife will be gone for a few hours and won't return home to find the original contents of the frig strewn all over the kitchen...
Best,
Dave
