A good source for rotational switches can be had in old thermostats which contain a mercury switch or two. An old thermostat contains a m...

This home built solar cooker is a parabolic solar reflector with a spit rod at the focus. A simple aligner post at the bottom front shows cl...

This easily built project recovers warm moist air from a clothes dryer that would otherwise be exhausted to the sub-zero outside. Energy i...