This effect we had talked about spookifying for a long time but never actually did it till this year. Relatively simple, we swapped out the supplied red and green silks for orange and black, added a couple pumpkin stickers and the effect looked great. We also experimented with small Halloween static window clings which worked as well as the stickers so you should have no problem finding suitable decorations for your effect.
Lets take a look a the Acrobatic Silks, its primarily a sucker routine for children and is well received. The kids will scream you are only turning the prop around until you make the silk go into the center. The effect could be performed surrounded, but wouldn't be fair to the people in back. Its a visual effect as well, and the props are examinable (although I can't imagine handing this prop out to kids). Play this effect up for what its worth and you will get a good response from it.
Couple cons, the effect is not repeatable, setup takes a minute or so (few seconds once you are experienced setting it up), and there is a possibility of an angle issue.
The effect is reasonably priced considering 3 silks are involved.
Show a wooden pole with 3 silks hanging down, 2 silks are the same color. The single odd silk is the acrobat, it can jump from end to end. You offer to prove the acrobatic silk really does jump! Pass the Pole behind your back, the odd color silk jumped from one side to the other. You repeat this a 2nd time. The odd silk has jumped back to it's original position! The kids go crazy yelling, they think you're just turning the pole around! Its not magic! This time the odd color silk jumps to the center of the pole. 3 - 18 inch Silks included. Great fun! NO Threads to worry about!