Interaction and actuation mechanisms used in scanning probe microscopies (SPM) have inherent potential for storage applications, but many unresolved conceptual and technical questions have precluded a thorough assessment of this potential so far. However, the intrinsic properties of SPM instrumentation and tip/sample interactions allow a number of important parameters and their ultimate values to be estimated. Coping with and possibly surpassing established technologies will require massive parallelism of SPM-type recording heads, a condition that might be satisfied in an elegant manner by using SPM-type, circulating piezoelectric flexural actuators. Operation of an entire array of recording heads will require highly precise micromechanical manufacturing and/or sophisticated control mechanisms. The resulting tolerance requirement can be relaxed by choosing long-range SPM interactions (Coulomb forces, capacitance, near-field optics, etc.). Furthermore, the interaction must allow a high recording speed. The restriction to read-only storage can facilitate exploratory work; the writing process in this case might be replaced by replication, similar to the techniques used in the production of compact disks.