1. A self-powered device, the device comprising: an energy collector configured to collect energy to power the self-powered device from an environment surrounding the self-powered device; a processor; and a memory comprising: instructions for selecting one of a plurality of modes of operation, wherein the plurality of modes of operation include: (i) a low-power mode of operation in which the self-powered device consumes less than a pre-determined or adaptively-determined amount of power and the self-powered device has less than full functionality, and (ii) and a high-power mode of operation in which the self-powered device consumes more than the pre-determined or adaptively-determined amount of power and the self-powered device has more functionality than in the low-power mode wherein the instructions for selecting one of a plurality of modes of operation include instructions for conserving power by alternating between the low-power mode of operation and the high-power mode of operation.