Discovered these interesting light up paper embellishments at Michael's last night at 50% off. Layers of foam and paper that either light up or light up with an illusion. This stern looking fellow turns in to:
The lights only last for 30 seconds. Great effect for costumes. There are light strings in this line as well. You can see this fellow here. My favorites are the haunted house and skull light string. The haunted house lights up in sequence one window at a time. My version is white light not yellow as shown. The only down side is they are delicate paper items and the effect doesn't last very long.