Many years ago, a dear friend's grandmother used to stitch all of us a "Christmas Eve Pillowcase" and she made them out of Christmas fabric. She put a pocket on the pillow and in order for us to receive a special gift from Santa Claus inside that pocket.... we "HAD TO SLEEP ON THAT MAGIC PILLOW CASE" on Christmas Eve. When we woke up Christmas morning, we had a small gift tucked inside the pocket - much like the Tooth Fairy does for those baby teeth!
Do this for adults too! Wrap your gift card or currency in wrapping and place it into the pocket and make them "Promise" not to open it until Christmas morning.