Today, a simple Arduino project that permit you to power on something connected to a 220v power using a simple relay.
Arduino – Automatic power on a 220v lamp (or whatever)
[Arduino] – Motion night lamp
Last night i destroyed everything in my kitchen to not turn on the light, and after that i decide to make this stupid motion night lamp.
[Arduino] Photoresistor and Mood Lamp
Easy way,
an RGB led with random colors that light on when light is off connected to Arduino Uno!