The document provides an overview of Utility Fog, a concept proposed by J. Storrs Hall involving nanobots called foglets that can link together to form any shape or structure. Foglets are proposed to be the size of human cells, with gripping arms that allow them to interconnect. Utility Fog could be used to form shelters, clothing, vehicles, and more, replacing the need for physical equipment. While it could provide great benefits, challenges remain around the size of individual foglets and lack of self-intelligence.