Halloween creepy party punch, freeze water in a surgical glove for a scary ice cube. I've always liked this idea. You can also fill the glove with the punch so the ice doesn't water it down. Note: make sure NOT to use the powdered gloves.
The Weeper: How many kids would dare approach a porch with this guy sitting there? Could be either an awesome prop or an amazing costume depending on how sadistic you're feeling toward the trick-or-treaters.