This is one of those ideas I wish I'd thought of! My kids love treasure hunts for their gifts, and my husband has come up with some good ones. With Giftventure, you hide your own present, sign up with their service, answer a few questions for personalization of the letters, and your child receives three letters in the mail with clues and puzzles to figure out; the third one leading them to the gift. You can choose among different characters (fairies, dragons, pirates) and themes (birthday, holiday). They are geared for children ages 4-12. I know my son would love it!