Gifts that generate more questions than answers are always prime for re-gifting. Here are a few excellent examples:
"Mommy, why is Santa wearing Grandma's lipstick? And her blush? And her blue eyeshadow? Will he still come to the house if I don't give him a hug?"
"Mommy, why does Santa look so angry? And smell like cough syrup?"
"Mommy, where is Santa's body?"