Take an plush owl. This one happens to be an Audobon Great Horned Owl. About 5 inches tall. (It also has a recorded "hoot" that plays when you press its abdomen...) Write a note, roll it up and enclose it, along with some glow-in-the-dark stars, in a "baby soda bottle" (a 2 liter bottle before it is blown up). Tie it securely to the owl's leg, attach a label and postage, and mail it to your kid at camp!