Raspberry Pi Switched LED Nightlight

thingiverse

This is an LED nightlight can be powered directly from Raspberry Pi GPIO provided you use only 1 LED and a low value resistor such as a 10 or 22 ohm giving something like 3v and 14ma. For brighter lights you can add more in series, but then you need to supply higher voltage and switch the light on and off with a transistor. This light works great with: 1 white/blue/pink light on 3v, with a 10-22ohm resistor straight from GPIO 2 red/orange lights on 5v, with a 39-47ohm resistor for each pair, switched with a transistor I've gone as high was 8 whites, or 6 reds powered from a 12v supply, but that's overkill for that small of a light.