Another tip, leave his packages plain except for the address and return address only with your first initial and last name. They are at the mercy of whoever is handing out the mail, and little hearts, x's and o's should be saved for the INSIDE of the package. Of course, if you want him to do a gazillion push-ups...
I am a navy wife, and I try my best to violate the heck out of this rule! Granted, my hubby had four years in the army before he switched and went through the navy's boot camp, so he was the crusty old man among the new recruits. That was a long time ago, but I still look out for those oh-so-special boxes to use for sending his packages to the ship.
The latest was a box for a case of KY Jelly
All over two sides were markings for KY in several languages, plus I printed out a pic of a tube of KY and slapped that on a third side. Another favorite was a full page newspaper ad for male get-it-up vitamins. I packaged his goodies in a regular box and then used the ad to completely wrap the box. I made sure that my mailing labels would not interfere with the funniest parts of the ad.
In reserve for future mailings are a box marked for Simple Solution Potty Training Aids (from a veterinary clinic) and a box for Boudreaux's Butt Paste (diaper rash cream).
My husband says I am evil because he has to hide in secluded places to open his mail. Of course, I temper my badness by sending him homemade cards with sappy haikus and by sending him 4"x6" photos of activities back home as postcards.