Ted Dewan of www.roadwitch.org.uk writes:
The original Road-Witch was an early experiment in 'folk' traffic calming. A Roadwitch is just a dummy, made with old clothes stuffed with leaves, newspapers, or rags. The crucial difference is that the 'head' is a road cone. When laying on the street, they form an effective means of slowing down traffic.
If you live in Britain or the USA, it’s generally the case that your local authority has failed to adequately protect you from people who forget they're operating lethal machinery in public. Setting up your own Roadwitch could be your first step in redressing the balance between motorists and 'unenhanced' humans who also use the roads.
Currently the resource site has information about all sorts of news from various places, photos of campaigns and traffic calming artwork. When I visited, Ted had highlighted this DIY traffic calming effort - "someone in the neighbourhood has had enough and has put in place a creative traffic calming system. It consists of two thick lengths of rope spread across the road. Surprisingly, traffic approaching these almost always slow to a crawl while crossing them."