This has often been historically envisaged as a guardian animal or a small supernatural being (puck, fairy, elf, and the like) or a ghost. In the developed world these beliefs have been, for the most part, discarded. A new layer of less-embodied superstition on the subject, however, has arisen around ley lines, feng shui and similar concepts, on the one hand, and urban leftover spaces, such as back alleys or gaps between buildings in some North-American downtown areas, on the other hand.[1]