Could energy consumption of electronic devices be further reduced by having peripherals which activate the sleeping processor rather than the processor continuously polling the external environment? A remote switch, for example, requires no current flow when off and yet instantly alerts the processor when needed. If the remote devices connect to identifiable input lines, the line which is activated could also identify the action required.
Ultra low power processors are in demand not only in medical application but also in general application. I believe the focus shall be more than just power management (aka sleep mode). The power consumption of full load shall be one of the many considerations.