A bird feeder that hangs from a pergola post near our back door has become a perfect home for paper wasps. These little critters are welcomed around here because they go after some of the nasty pests that attack my garden.
They also leave behind their gorgeous nests which they construct from plant fiber and saliva to make paper. I've used this lovely material for collage in a couple of my books. The tree branch on the cover of Scoot! is made from wasp nest paper.
I shot this little video of the wasps at work. Sorry for the jerky quality--I don't have a tripod.