Wilf's Pummer
Wilf posted a neat, very efficient "pummer" circuit powered by one of his versions of a nocturnal solar engine (in particular, the SIMD1 / Solar Regulator):
Here's Wilf's quick description of his pummer (the small bit of circuitry in the right part of the above diagram:
The PowerSaver Flasher uses capacitive output coupling to produce brighter shorter flashes and has a much lower average current drain than standard bicore or 74HC14 flashers. The PS Flasher with one LED circuit (2 LEDs) runs all night from a 1F capacitor charged to 5.5V. Up to 12 LEDs can be controlled with one 74HC14 flasher and probably would run for 2 hours from a full charge. Use a range of timing resistors between 1M and 4.7M for each oscillator to give a random light show appearance.
Notes
I built the PS Flasher part of the circuit with a regulated 5v power supply, and found that using the component values listed caused the LED to flicker weakly and rapidly. Using a 330uF capacitor instead of 22uF significantly increase the brightness of the flashes, while making it flash at about 2Hz. It would appear it is not a simple matter of using capacitors of large values. Using a 1000uF capacitor the LED was weaker. However YMMV. - user:freespace