Power has become a limiting factor in many applications. Specially in portable products, wireless applications and temperature limited products and systems. Therefore it is useful to investigate and develop really low power, “ultra” low power devices ( Integrated circuits and modules) that can be used to build more complex systems. techniques such as low voltage devices, sub-threshold CMOS circuits, energy harvesting etc. all play a part in the design of such devices. It is a fascinating area of design. Over the past few years the techteam at Signal Processing Group Inc, has been involved in the design of low power circuits for use in RFID and 1.2V battery powered systems. Some of this work is available for discussion. For details or for help in the design of these type of devices please contact SPG at http://www.signalpro.biz.