"Dirty Thunderstorm" of death

Not particularly Halloween-y, but certainly scary... the "dirty thunderstorm". Created by Chile's erupting Chaitén volcano, these "little understood storms may be sparked when rock fragments, ash, and ice particles in the plume collide to produce static charges--just as ice particles collide to create charge in regular thunderstorms." If only I could create one for my annual yard haunt.

Thunder and lightning machine comparison

For anyone who is thinking of buying a thunder and lightning simulator this website will be an invaluable resource. Their comparisons and reviews of machines by more than a dozen companies will help you choose the right one.