Give this spirited specter a little push to get it moving, and let partygoers conjure up guesses as to what keeps it floating eerily just above the floor.
Tape 2 pieces of 12-inch-long white craft wire in criss-cross fashion to a 14-inch square of double-layer white tissue paper.
Trim the paper into a circle, cutting through the wire, then flip over the tissue and set it over a lemon. Use your hands to loosely mold the center of the paper over the lemon to form a ghost head, then use a black marker to add facial details.
Concealing the lemon, place the ghost on the floor or a table and give it a nudge to set it in motion.