When my kids were younger my neighbor would take his raked up leaves and fill black garbage bags of various sizes, cut a few bent sticks and create a army of spiders walking toward the street for Halloween fun.
I showed up one year with some lighting, five bucks worth of webbing from the Halloween store and we really set the thing off.
It freaked someone out, though. A group came by one night and tore it all to shit, broke my lighting equipment and set fire to his leaf bags.
Bastards!
I forgot to add about my daughter's line of questions the day after ...
"Daddy, are scorpions stronger than spiders?"
And after more questions from me, she wanted to re-do it again, but with scorpions.
Unfortunately, my fancy bright lights were destroyed. And the neighbor was discouraged.