Got the costumes? Check. Bought the candy? Check. Hung the skeleton from the tree? Check. But do you have the uneasy feeling that something is missing from your Halloween setup? Is it just not scary enough? How about filling your doorway, garage or yard with fog, the thick white kind that rolls in when evil spirits are on the move? You can go the minimalist route with a small foggy crystal ball or smoky skull, or go all out with a professional quality fog machine. Prices range from fairly affordable to fairly steep if you want the big daddies. There’s even a website devoted to the subject of fog machines that answers any question you might have. Even Target sells one. MusicOutfitters has professional quality machines in a variety of sizes and prices, and their website has a handy user’s guide.