The rapid evolution of micro-nanoelectronics has led to unprecedented opportunities to implement ultra-miniaturized electronic systems and directly interface them with biological systems. Thanks to the huge possibilities in terms of design space, nanoscale microelectronic circuits can allow the implementation of incredibly compact electronic systems with very complex functionalities, including sensing, actuating, processing, and communicating, which could be potentially employed in countless new opportunities to realize “smart” (i.e. able to perform complex functions) human–machine interfaces in both directions, from human to machine (including also humanoid robots) and vice versa, and so closing the information loop in order to allow bidirectional interactions. However, the encumbrance of the contact-based interfaces could greatly limit the exploitation of the emerging plethora of potential opportunities to build smart human–machine interfaces. To overcome these limitations, there is growing interest in autonomous electronic systems that, in general, could be expected to be contactless, self- or remotely powered, ultra-miniaturized, non- or minimally invasive with negligible side effects, biocompatible, eco-friendly (i.e. green), low-cost, and so on, that we could refer to as zero-power [1] and more generally as zero-impact electronic systems, sometimes also referred to as “smart dust” [2]. These future and emerging technologies are an extremely active macro-area of research [3] that, in spite of enormous recent progress, is still at the early stage. In this general context of grand challenges, the current silicon-based microelectronic technologies can provide a huge range of opportunities for delivering potential solutions that could respond, at least in part, to the wishful thinking for the most effective solutions of the future.