Doc carries a Computer Diagnostic Unit; a compact computer which has advanced diagnostics and maintenance functions, along with sensory and computer linkage capability. The CDU acts as a focus for Doc's implant power, and also as a storage facility for his "tweakers" (Pathfinder, Tripwire, Firefly, Searchlight, Lifeline, and Pixel). His "tweaker" computer programs are part of his personality and offer capabilities far beyond any normal computer program, virus, or worm. His implant gives him control over his "tweakers" via simple verbal communication, and his "tweakers" give Doc control over any computer system.