A true hacker is an individual who can achieve miracles by appropriating, modifying, or "kludging" existing resources (devices, hardware, software, or anything within reach) to suit other purposes, often in an ingenious fashion. Gifted hackers can be thought of as transmutation or collage artists. They take everything from streamlined commercial products to bits of junk as their raw materials, leveraging the development and cost efficiencies of mass production as they modify established technology to serve their needs. Their work often juxtaposes unrelated modules in shotgun marriages, transforming off-the-shelf "lead" into technological "gold." In this special issue, we turn our attention to this positive connotation of the hacker from the perspective of pervasive computing.