Providing efficient and clean power is a challenge for devices that range from the micro to macro in scale. Although there has been significant progress in the development of micro-, meso-, and macro-scale power supplies and technologies, realization of many devices is limited by the inability of power supplies to scale with the diminishing sizes of CMOS-based technology. Here, the authors provide an overview of piezoelectric energy harvesting technology along with a discussion of proof of concept devices, relevant governing equations, and figures of merit. They present two case studies: (a) energy capture from the operation of a novel shear and elastic modulus indentation device subjected to applied voltage and (b) energy capture from vibrating commercial bimorph piezoelectric structures mounted on household appliances. Lastly, areas of development needed for realization of commercial energy harvesting devices are suggested. (Contains 6 tables and 7 figures.)