Using motion detectors and an Arduino you can trigger lights, fans, or even an pneumatically controlled cleaver-wielding clown to help add your house to the “if you dare” list. There are ...

When everything’s plugged in, this is how your Arduino, motion sensor, and power relay should look. Jeremy S. Cook. Plug the male-to-female jumper wires into the motion sensor pins.

If you've always wanted to try to build an Arduino project, this may be a great way to start. Matt Williamson built a tiny, Arduino-based motion sensor that will SMS you when something moves by ...