Pete wrote:

Is it possible to power an LED from a light switch (live only connections,
and possible earth) so an illuminated LED can indicate if the light is on or
off?




Yes. Its horrendously inefficinet tho. You need a diode in addition to
the LED wired in series, and a series resistor. about 22Kohms will do
and at LEAST 2W rated. It will get hot.

Alternatively a capacitor can be used, but tis late and I can't be
bothered to calculate teh value...,