Why not try these ideas for Halloween?
Fly and Spider Ice Cubes
You can make ice cubes with plastic flies and spiders inside (you can normally find them in joke shops).
Dead Man's Hand
You can make a frozen dead man's hand by filling a rubber glove full of raspberries and cranberry juice and freezing it. When it's party time, run warm water over the gloves very briefly - just long enough to loosen the gloves from the ice - and carefully peel them off the frozen hand. The ice fingers break off easily, but don't worry - that's okay - the disembodied digits just add to the "zombie" effect.
Don't use the hand in a bowl of punch or let anyone eat it as some people are allergic to latex!