Introduction" explains energy harvesting, twelve technologies - materials, capability, market needs overall. Learn systems aspects, parameters, practicalities of the triboelectric series and the troublesome variety of influencing factors. Four modes are looked at in great detail, electrostatic harvesting generally and lessons for the future. Chapter 3 details "Early Commercialisation: Self-Powered Filters, Toys and Novelties" already sold and what comes next . Chapter 4 analyses "Materials Virtuosity: Self-healing, Transparent, Stretchable, Hydrophobic, Biocompatible and More". IDTechEx presents new ideas and benchmarking.