Oxide on Si wafers can be manipulated by a scanning probe microscope (SPM) operated in the electrical conductivity mode (ECM), by several distinctly different mechanisms (i.e. anodic oxidation, dielectric break-down, and lateral transport of silicaceous species). The mechanisms can, in principle, support the full sequence of write-read-erase-rewrite operations, and thus a next-generation data storage technology. Bit size ranges from 10 to 50 nm; read-write speeds are currently limited by single probe AFM operation. Electrically conducting diamond-like (DLC) films can be synthesised by an ion-beam assisted CVD route. Such films can be nano-machined with a probe by an ECM method. Present evidence suggests that local heating causes oxidation and prompt conversion to CO2. The process may be useful for fabricating stamps for nano-scale templating. Local deposition of thermal energy may also cause formation of a metastable low-density carbon phase. The phase is stable in vacuum, but will 'collapse' when oxygen is available, at a slow kinetic rate. (C) 2003 Elsevier B.V. All rights reserved.