:skull: Download various halloween sound effects, screams, moans, chains, etc and burn them onto an Mp3 cd. Then set your cd player to loop all the sounds.
Blow bubbles into a bowl with a straw for the sound of ooze or a laboratory.
:skull: Get your local teenagers to scream into a microphone.
:skull: Create a Laser show effect by taping glow sticks to a ceiling fan turned on LOW. (May scratch the finish on your fan, *fair warning!*
:skull: Glamorous Spiders– a really cheap idea- buy a bag of Spider rings from the dollar store, paint them with various colors of nail polish- just a bit of glam, sprinkle on some glitter if desired and scatter them around your house. Double stick tape works wonders on sticking these to walls, drapes, and the backs of unsuspecting guests.