Wired:

The Baltimore Wastewater Treatment Plant put out a call for “extreme spider” help in 2009, when a giant spiderweb covered almost 4 acres of their facility. Scientists eventually estimated over 107 million spiders were living in the structure, with densities of 35,176 spiders per m³ in spots.

In honour of Halloween, I’m going to leave this right here for you. Thanks to Brian Webster for the link.